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<span>Emissions</span> </div> </a> <ul id="toc-Emissions-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Applications" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Applications"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Applications</span> </div> </a> <ul id="toc-Applications-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Designs" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Designs"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Designs</span> </div> </a> <button aria-controls="toc-Designs-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Designs subsection</span> </button> <ul id="toc-Designs-sublist" class="vector-toc-list"> <li id="toc-Inlet_port_variations" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Inlet_port_variations"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Inlet port variations</span> </div> </a> <ul id="toc-Inlet_port_variations-sublist" class="vector-toc-list"> <li id="toc-Piston-controlled_inlet_port" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Piston-controlled_inlet_port"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1.1</span> <span>Piston-controlled inlet port</span> </div> </a> <ul id="toc-Piston-controlled_inlet_port-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Reed_inlet_valve" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Reed_inlet_valve"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1.2</span> <span>Reed inlet valve</span> </div> </a> <ul id="toc-Reed_inlet_valve-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Rotary_inlet_valve" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Rotary_inlet_valve"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1.3</span> <span>Rotary inlet valve</span> </div> </a> <ul id="toc-Rotary_inlet_valve-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Scavenging_variations" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Scavenging_variations"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Scavenging variations</span> </div> </a> <ul id="toc-Scavenging_variations-sublist" class="vector-toc-list"> <li id="toc-Cross-flow_scavenging" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Cross-flow_scavenging"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.1</span> <span>Cross-flow scavenging</span> </div> </a> <ul id="toc-Cross-flow_scavenging-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Loop_scavenging" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Loop_scavenging"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.2</span> <span>Loop scavenging</span> </div> </a> <ul id="toc-Loop_scavenging-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Uniflow_scavenging" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Uniflow_scavenging"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.3</span> <span>Uniflow scavenging</span> </div> </a> <ul id="toc-Uniflow_scavenging-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Stepped_piston_engine" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Stepped_piston_engine"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Stepped piston engine</span> </div> </a> <ul id="toc-Stepped_piston_engine-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Power-valve_systems" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Power-valve_systems"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Power-valve systems</span> </div> </a> <ul id="toc-Power-valve_systems-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Direct_injection" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Direct_injection"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Direct injection</span> </div> </a> <ul id="toc-Direct_injection-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Two-stroke_reversibility" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Two-stroke_reversibility"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Two-stroke reversibility</span> </div> </a> <ul id="toc-Two-stroke_reversibility-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Further_reading" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Further_reading"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>Further reading</span> </div> </a> <ul id="toc-Further_reading-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Table of Contents" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" 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Available in 51 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-51" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">51 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D8%AD%D8%B1%D9%83_%D8%B4%D9%88%D8%B7%D9%8A%D9%86" title="محرك شوطين – Arabic" lang="ar" hreflang="ar" data-title="محرك شوطين" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/%C4%B0kitaktl%C4%B1_m%C3%BCh%C9%99rrik" title="İkitaktlı mühərrik – Azerbaijani" lang="az" hreflang="az" data-title="İkitaktlı mühərrik" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%94%D0%B2%D1%83%D1%82%D0%B0%D0%BA%D1%82%D0%BE%D0%B2_%D0%B4%D0%B2%D0%B8%D0%B3%D0%B0%D1%82%D0%B5%D0%BB" title="Двутактов двигател – Bulgarian" lang="bg" hreflang="bg" data-title="Двутактов двигател" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Motor_de_dos_temps" title="Motor de dos temps – Catalan" lang="ca" hreflang="ca" data-title="Motor de dos temps" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Dvoudob%C3%BD_spalovac%C3%AD_motor" title="Dvoudobý spalovací motor – Czech" lang="cs" hreflang="cs" data-title="Dvoudobý spalovací motor" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Totaktsmotor" title="Totaktsmotor – Danish" lang="da" hreflang="da" data-title="Totaktsmotor" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Zweitaktmotor" title="Zweitaktmotor – German" lang="de" hreflang="de" data-title="Zweitaktmotor" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Motor_de_dos_tiempos" title="Motor de dos tiempos – Spanish" lang="es" hreflang="es" data-title="Motor de dos tiempos" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Dutakta_motoro" title="Dutakta motoro – Esperanto" lang="eo" hreflang="eo" data-title="Dutakta motoro" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Bi_aldiko_eztanda-motorra" title="Bi aldiko eztanda-motorra – Basque" lang="eu" hreflang="eu" data-title="Bi aldiko eztanda-motorra" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%85%D9%88%D8%AA%D9%88%D8%B1_%D8%AF%D9%88%D8%B2%D9%85%D8%A7%D9%86%D9%87" title="موتور دوزمانه – Persian" lang="fa" hreflang="fa" data-title="موتور دوزمانه" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Moteur_%C3%A0_deux_temps" title="Moteur à deux temps – French" lang="fr" hreflang="fr" data-title="Moteur à deux temps" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-fy mw-list-item"><a href="https://fy.wikipedia.org/wiki/Twataktmotor" title="Twataktmotor – Western Frisian" lang="fy" hreflang="fy" data-title="Twataktmotor" data-language-autonym="Frysk" data-language-local-name="Western Frisian" class="interlanguage-link-target"><span>Frysk</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Inneall_dh%C3%A1_bhuille" title="Inneall dhá bhuille – Irish" lang="ga" hreflang="ga" data-title="Inneall dhá bhuille" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Motor_a_dous_tempos" title="Motor a dous tempos – Galician" lang="gl" hreflang="gl" data-title="Motor a dous tempos" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/2%ED%96%89%EC%A0%95_%EA%B8%B0%EA%B4%80" title="2행정 기관 – Korean" lang="ko" hreflang="ko" data-title="2행정 기관" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%A6%E0%A5%8D%E0%A4%B5%E0%A4%BF%E0%A4%98%E0%A4%BE%E0%A4%A4_%E0%A4%87%E0%A4%82%E0%A4%9C%E0%A4%A8" title="द्विघात इंजन – Hindi" lang="hi" hreflang="hi" data-title="द्विघात इंजन" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Dvotaktni_motor" title="Dvotaktni motor – Croatian" lang="hr" hreflang="hr" data-title="Dvotaktni motor" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Motor_bakar_dua_langkah" title="Motor bakar dua langkah – Indonesian" lang="id" hreflang="id" data-title="Motor bakar dua langkah" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Motore_a_due_tempi" title="Motore a due tempi – Italian" lang="it" hreflang="it" data-title="Motore a due tempi" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%9E%D7%97%D7%96%D7%95%D7%A8_%D7%A9%D7%AA%D7%99_%D7%A4%D7%A2%D7%99%D7%9E%D7%95%D7%AA" title="מחזור שתי פעימות – Hebrew" lang="he" hreflang="he" data-title="מחזור שתי פעימות" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/K%C3%A9t%C3%BCtem%C5%B1_motor" title="Kétütemű motor – Hungarian" lang="hu" hreflang="hu" data-title="Kétütemű motor" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mr mw-list-item"><a href="https://mr.wikipedia.org/wiki/%E0%A4%9F%E0%A5%82_%E0%A4%B8%E0%A5%8D%E0%A4%9F%E0%A5%8D%E0%A4%B0%E0%A5%8B%E0%A4%95_%E0%A4%87%E0%A4%82%E0%A4%9C%E0%A4%BF%E0%A4%A8" title="टू स्ट्रोक इंजिन – Marathi" lang="mr" hreflang="mr" data-title="टू स्ट्रोक इंजिन" data-language-autonym="मराठी" data-language-local-name="Marathi" class="interlanguage-link-target"><span>मराठी</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Enjin_dua_lejang" title="Enjin dua lejang – Malay" lang="ms" hreflang="ms" data-title="Enjin dua lejang" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Tweetaktmotor" title="Tweetaktmotor – Dutch" lang="nl" hreflang="nl" data-title="Tweetaktmotor" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/2%E3%82%B9%E3%83%88%E3%83%AD%E3%83%BC%E3%82%AF%E6%A9%9F%E9%96%A2" title="2ストローク機関 – Japanese" lang="ja" hreflang="ja" data-title="2ストローク機関" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Totaktsmotor" title="Totaktsmotor – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Totaktsmotor" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Totaktsmotor" title="Totaktsmotor – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Totaktsmotor" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Ikki_taktli_dvigatel" title="Ikki taktli dvigatel – Uzbek" lang="uz" hreflang="uz" data-title="Ikki taktli dvigatel" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Silnik_dwusuwowy" title="Silnik dwusuwowy – Polish" lang="pl" hreflang="pl" data-title="Silnik dwusuwowy" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Motor_de_dois_tempos" title="Motor de dois tempos – Portuguese" lang="pt" hreflang="pt" data-title="Motor de dois tempos" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ksh mw-list-item"><a href="https://ksh.wikipedia.org/wiki/Zweitaktmotor" title="Zweitaktmotor – Colognian" lang="ksh" hreflang="ksh" data-title="Zweitaktmotor" data-language-autonym="Ripoarisch" data-language-local-name="Colognian" class="interlanguage-link-target"><span>Ripoarisch</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Motor_%C3%AEn_doi_timpi" title="Motor în doi timpi – Romanian" lang="ro" hreflang="ro" data-title="Motor în doi timpi" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%94%D0%B2%D1%83%D1%85%D1%82%D0%B0%D0%BA%D1%82%D0%BD%D1%8B%D0%B9_%D0%B4%D0%B2%D0%B8%D0%B3%D0%B0%D1%82%D0%B5%D0%BB%D1%8C" title="Двухтактный двигатель – Russian" lang="ru" hreflang="ru" data-title="Двухтактный двигатель" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sat mw-list-item"><a href="https://sat.wikipedia.org/wiki/%E1%B1%B5%E1%B1%9F%E1%B1%A8-%E1%B1%A5%E1%B1%B4%E1%B1%A8%E1%B1%9A%E1%B1%A0_%E1%B1%A4%E1%B1%B8%E1%B1%A1%E1%B1%9F%E1%B1%B1" title="ᱵᱟᱨ-ᱥᱴᱨᱚᱠ ᱤᱸᱡᱟᱱ – Santali" lang="sat" hreflang="sat" data-title="ᱵᱟᱨ-ᱥᱴᱨᱚᱠ ᱤᱸᱡᱟᱱ" data-language-autonym="ᱥᱟᱱᱛᱟᱲᱤ" data-language-local-name="Santali" class="interlanguage-link-target"><span>ᱥᱟᱱᱛᱟᱲᱤ</span></a></li><li class="interlanguage-link interwiki-sc mw-list-item"><a href="https://sc.wikipedia.org/wiki/Motore_a_duos_tempos" title="Motore a duos tempos – Sardinian" lang="sc" hreflang="sc" data-title="Motore a duos tempos" data-language-autonym="Sardu" data-language-local-name="Sardinian" class="interlanguage-link-target"><span>Sardu</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B6%AF%E0%B7%99%E0%B6%B4%E0%B7%84%E0%B6%BB_%E0%B6%91%E0%B6%B1%E0%B7%8A%E0%B6%A2%E0%B7%92%E0%B6%B1%E0%B7%8A" title="දෙපහර එන්ජින් – Sinhala" lang="si" hreflang="si" data-title="දෙපහර එන්ජින්" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Two-stroke_engine" title="Two-stroke engine – Simple English" lang="en-simple" hreflang="en-simple" data-title="Two-stroke engine" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Dvojdob%C3%BD_motor" title="Dvojdobý motor – Slovak" lang="sk" hreflang="sk" data-title="Dvojdobý motor" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Dvotaktni_motor" title="Dvotaktni motor – Slovenian" lang="sl" hreflang="sl" data-title="Dvotaktni motor" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-szl mw-list-item"><a href="https://szl.wikipedia.org/wiki/Dwusuwowy_motor" title="Dwusuwowy motor – Silesian" lang="szl" hreflang="szl" data-title="Dwusuwowy motor" data-language-autonym="Ślůnski" data-language-local-name="Silesian" class="interlanguage-link-target"><span>Ślůnski</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D8%A8%D8%B2%D9%88%DB%8E%D9%86%DB%95%D8%B1%DB%8C_%D8%AF%D9%88%D9%88_%DA%BE%DB%95%D9%86%DA%AF%D8%A7%D9%88%DB%8C" title="بزوێنەری دوو ھەنگاوی – Central Kurdish" lang="ckb" hreflang="ckb" data-title="بزوێنەری دوو ھەنگاوی" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%94%D0%B2%D0%BE%D1%82%D0%B0%D0%BA%D1%82%D0%BD%D0%B8_%D0%BC%D0%BE%D1%82%D0%BE%D1%80" title="Двотактни мотор – Serbian" lang="sr" hreflang="sr" data-title="Двотактни мотор" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Kaksitahtimoottori" title="Kaksitahtimoottori – Finnish" lang="fi" hreflang="fi" data-title="Kaksitahtimoottori" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Tv%C3%A5taktsmotor" title="Tvåtaktsmotor – Swedish" lang="sv" hreflang="sv" data-title="Tvåtaktsmotor" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%A2%E0%B8%99%E0%B8%95%E0%B9%8C%E0%B8%AA%E0%B8%AD%E0%B8%87%E0%B8%88%E0%B8%B1%E0%B8%87%E0%B8%AB%E0%B8%A7%E0%B8%B0" title="เครื่องยนต์สองจังหวะ – Thai" lang="th" hreflang="th" data-title="เครื่องยนต์สองจังหวะ" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/%C4%B0ki_zamanl%C4%B1_motor" title="İki zamanlı motor – Turkish" lang="tr" hreflang="tr" data-title="İki zamanlı motor" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%94%D0%B2%D0%BE%D1%82%D0%B0%D0%BA%D1%82%D0%BD%D0%B8%D0%B9_%D0%B4%D0%B2%D0%B8%D0%B3%D1%83%D0%BD" title="Двотактний двигун – Ukrainian" lang="uk" hreflang="uk" data-title="Двотактний двигун" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D8%AF%D9%88_%D8%A7%D8%B3%D9%B9%D8%B1%D9%88%DA%A9_%DA%A9%D8%A7_%D8%A7%D9%86%D8%AC%D9%86" title="دو اسٹروک کا انجن – Urdu" lang="ur" hreflang="ur" data-title="دو اسٹروک کا انجن" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/%C4%90%E1%BB%99ng_c%C6%A1_hai_k%E1%BB%B3" title="Động cơ hai kỳ – Vietnamese" lang="vi" 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.hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">"2-cycle" redirects here. For the mathematical concept, see <a href="/wiki/Cyclic_permutation" title="Cyclic permutation">Cyclic permutation</a>.</div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Two-Stroke_Engine.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/3/33/Two-Stroke_Engine.gif" decoding="async" width="165" height="287" class="mw-file-element" data-file-width="165" data-file-height="287" /></a><figcaption>Animation of a two-stroke engine</figcaption></figure> <p>A <b>two-stroke</b> (or <b>two-stroke cycle</b>) <b>engine</b> is a type of <a href="/wiki/Internal_combustion_engine" title="Internal combustion engine">internal combustion engine</a> that completes a <a href="/wiki/Thermodynamic_power_cycle" class="mw-redirect" title="Thermodynamic power cycle">power cycle</a> with two strokes of the <a href="/wiki/Piston" title="Piston">piston</a> (one up and one down movement) in one revolution of the crankshaft in contrast to a <a href="/wiki/Four-stroke_engine" title="Four-stroke engine">four-stroke engine</a> which requires four strokes of the piston in two crankshaft revolutions to complete a power cycle. During the stroke from bottom dead center to top dead center, the end of the exhaust/intake (or <a href="/wiki/Scavenging_(automotive)" class="mw-redirect" title="Scavenging (automotive)">scavenging</a>) is completed along with the compression of the mixture. The second stroke encompasses the combustion of the mixture, the expansion of the burnt mixture and, near bottom dead center, the beginning of the scavenging flows. </p><p>Two-stroke engines often have a higher <a href="/wiki/Power-to-weight_ratio" title="Power-to-weight ratio">power-to-weight ratio</a> than a four-stroke engine, since their power stroke occurs twice as often. Two-stroke engines can also have fewer <a href="/wiki/Moving_parts" title="Moving parts">moving parts</a>, and thus be cheaper to manufacture and weigh less. In countries and regions with stringent emissions regulation, two-stroke engines have been phased out in automotive and motorcycle uses. In regions where regulations are less stringent, small displacement two-stroke engines remain popular in <a href="/wiki/Moped" title="Moped">mopeds</a> and motorcycles.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> They are also used in power tools such as <a href="/wiki/Chainsaw" title="Chainsaw">chainsaws</a> and <a href="/wiki/Leaf_blower" title="Leaf blower">leaf blowers</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first commercial two-stroke engine involving cylinder compression is attributed to <a href="/wiki/Scotland" title="Scotland">Scottish</a> engineer <a href="/wiki/Dugald_Clerk" title="Dugald Clerk">Dugald Clerk</a>, who patented his design in 1881.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> However, unlike most later two-stroke engines, his had a separate charging cylinder. The <a href="/wiki/Crankcase" title="Crankcase">crankcase</a>-scavenged engine, employing the area below the piston as a charging pump, is generally credited to Englishman <a href="/wiki/Joseph_Day_(inventor)" title="Joseph Day (inventor)">Joseph Day</a>.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> On 31 December 1879, <a href="/wiki/Germany" title="Germany">German</a> <a href="/wiki/Inventor" class="mw-redirect" title="Inventor">inventor</a> <a href="/wiki/Karl_Benz" class="mw-redirect" title="Karl Benz">Karl Benz</a> produced a two-stroke gas engine, for which he received a patent in 1880 in Germany. The first truly practical two-stroke engine is attributed to Yorkshireman <a href="/wiki/Alfred_Angas_Scott" title="Alfred Angas Scott">Alfred Angas Scott</a>, who started producing <a href="/wiki/Two_cylinder" class="mw-redirect" title="Two cylinder">twin-cylinder</a> <a href="/wiki/Water_cooled" class="mw-redirect" title="Water cooled">water-cooled</a> <a href="/wiki/Motorcycle" title="Motorcycle">motorcycles</a> in 1908.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Two-stroke <a href="/wiki/Gasoline" title="Gasoline">gasoline</a> engines with electrical <a href="/wiki/Spark_ignition" class="mw-redirect" title="Spark ignition">spark ignition</a> are particularly useful in lightweight or portable applications such as <a href="/wiki/Chainsaws" class="mw-redirect" title="Chainsaws">chainsaws</a> and motorcycles. However, when weight and size are not an issue, the cycle's potential for high <a href="/wiki/Thermodynamic_efficiency" class="mw-redirect" title="Thermodynamic efficiency">thermodynamic efficiency</a> makes it ideal for <a href="/wiki/Diesel_fuel" title="Diesel fuel">diesel</a> <a href="/wiki/Compression_ignition" class="mw-redirect" title="Compression ignition">compression ignition</a> engines operating in large, weight-insensitive applications, such as <a href="/wiki/Marine_propulsion" title="Marine propulsion">marine propulsion</a>, <a href="/wiki/Locomotive" title="Locomotive">railway locomotives</a>, and <a href="/wiki/Diesel_generator" title="Diesel generator">electricity generation</a>. In a two-stroke engine, the exhaust gases transfer less heat to the cooling system than a four-stroke, which means more energy to drive the piston, and if present, a turbocharger. </p> <div class="mw-heading mw-heading2"><h2 id="Emissions">Emissions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=2" title="Edit section: Emissions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Crankcase-compression two-stroke engines, such as common small gasoline-powered engines, are lubricated by a <a href="/wiki/Petroil" class="mw-redirect" title="Petroil">petroil</a> mixture in a <a href="/wiki/Total-loss_oiling_system" title="Total-loss oiling system">total-loss system</a>. Oil is mixed in with their petrol fuel beforehand, in a fuel-to-oil ratio of around 32:1. This oil then forms emissions, either by being burned in the engine or as droplets in the exhaust, historically resulting in more exhaust emissions, particularly hydrocarbons, than four-stroke engines of comparable power output. The combined opening time of the intake and exhaust ports in some two-stroke designs can also allow some amount of unburned fuel vapors to exit in the exhaust stream. The high combustion temperatures of small, air-cooled engines may also produce <a href="/wiki/NOx" title="NOx">NO<sub>x</sub></a> emissions. </p> <div class="mw-heading mw-heading2"><h2 id="Applications">Applications</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=3" title="Edit section: Applications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Saab_96_Sport.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Saab_96_Sport.JPG/220px-Saab_96_Sport.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Saab_96_Sport.JPG/330px-Saab_96_Sport.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/49/Saab_96_Sport.JPG/440px-Saab_96_Sport.JPG 2x" data-file-width="4608" data-file-height="3456" /></a><figcaption>1966 <a href="/wiki/Saab_Sport" class="mw-redirect" title="Saab Sport">Saab Sport</a></figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Pocketbike_dirtbike.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Pocketbike_dirtbike.jpg/170px-Pocketbike_dirtbike.jpg" decoding="async" width="170" height="170" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Pocketbike_dirtbike.jpg/255px-Pocketbike_dirtbike.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/31/Pocketbike_dirtbike.jpg/340px-Pocketbike_dirtbike.jpg 2x" data-file-width="657" data-file-height="657" /></a><figcaption>A two-stroke minibike</figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:BritishSeagull2.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/BritishSeagull2.JPG/170px-BritishSeagull2.JPG" decoding="async" width="170" height="302" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/BritishSeagull2.JPG/255px-BritishSeagull2.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/17/BritishSeagull2.JPG/340px-BritishSeagull2.JPG 2x" data-file-width="1584" data-file-height="2816" /></a><figcaption>Lateral view of a two-stroke Forty series <a href="/wiki/British_Seagull" title="British Seagull">British Seagull</a> <a href="/wiki/Outboard_engine" class="mw-redirect" title="Outboard engine">outboard engine</a>, the serial number dates it to 1954/1955</figcaption></figure> <p>Two-stroke gasoline engines are preferred when mechanical simplicity, light weight, and high <a href="/wiki/Power-to-weight_ratio" title="Power-to-weight ratio">power-to-weight ratio</a> are design priorities. By mixing oil with fuel, they can operate in any orientation as the <a href="/wiki/Sump" title="Sump">oil reservoir</a> does not depend on gravity. </p><p>A number of mainstream automobile manufacturers have used two-stroke engines in the past, including the Swedish <a href="/wiki/Saab_Automobile" title="Saab Automobile">Saab</a>, German manufacturers <a href="/wiki/DKW" title="DKW">DKW</a>, <a href="/wiki/Auto-Union" class="mw-redirect" title="Auto-Union">Auto-Union</a>, <a href="/wiki/VEB_Sachsenring_Automobilwerke_Zwickau" class="mw-redirect" title="VEB Sachsenring Automobilwerke Zwickau">VEB Sachsenring Automobilwerke Zwickau</a>, <a href="/wiki/VEB_Automobilwerk_Eisenach" class="mw-redirect" title="VEB Automobilwerk Eisenach">VEB Automobilwerk Eisenach</a>, and <a href="/wiki/Simson_(company)" title="Simson (company)">VEB Fahrzeug- und Jagdwaffenwerk</a>, and Polish manufacturers <a href="/wiki/Fabryka_Samochod%C3%B3w_Osobowych" title="Fabryka Samochodów Osobowych">FSO</a> and <a href="/wiki/Fabryka_Samochod%C3%B3w_Ma%C5%82olitra%C5%BCowych" title="Fabryka Samochodów Małolitrażowych">FSM</a>. The Japanese manufacturers <a href="/wiki/Suzuki" title="Suzuki">Suzuki</a> and <a href="/wiki/Subaru" title="Subaru">Subaru</a> did the same in the 1970s.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Production of two-stroke cars ended in the 1980s in the West, due to increasingly stringent <a href="/wiki/Clean_Air_Act_(United_States)" title="Clean Air Act (United States)">regulation of air pollution</a>.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Eastern_Bloc" title="Eastern Bloc">Eastern Bloc</a> countries continued until around 1991, with the <a href="/wiki/Trabant" title="Trabant">Trabant</a> and <a href="/wiki/Wartburg_(marque)" title="Wartburg (marque)">Wartburg</a> in East Germany. </p><p>Two-stroke engines are still found in a variety of small propulsion applications, such as <a href="/wiki/Outboard_motor" title="Outboard motor">outboard motors</a>, small on- and <a href="/wiki/Dirt_bike" class="mw-redirect" title="Dirt bike">off-road</a> <a href="/wiki/Motorcycle" title="Motorcycle">motorcycles</a>, <a href="/wiki/Moped" title="Moped">mopeds</a>, <a href="/wiki/Scooter_(motorcycle)" title="Scooter (motorcycle)">motor scooters</a>, <a href="/wiki/Motorized_bicycle" title="Motorized bicycle">motorized bicycles</a>, <a href="/wiki/Tuk-tuk" class="mw-redirect" title="Tuk-tuk">tuk-tuks</a>, <a href="/wiki/Snowmobile" title="Snowmobile">snowmobiles</a>, <a href="/wiki/Go-kart" title="Go-kart">go-karts</a>, <a href="/wiki/Radio-controlled_car" title="Radio-controlled car">RC cars</a>, <a href="/wiki/Ultralight" class="mw-redirect" title="Ultralight">ultralight</a> and <a href="/wiki/Model_airplane" class="mw-redirect" title="Model airplane">model</a> airplanes. Particularly in developed countries, pollution regulations have meant that their use for many of these applications is being phased out. <a href="/wiki/Honda_Motor_Company" class="mw-redirect" title="Honda Motor Company">Honda</a>,<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> for instance, ceased selling two-stroke off-road motorcycles in the United States in 2007, after abandoning road-going models considerably earlier. </p><p>Due to their high power-to-weight ratio and ability to be used in any orientation, two-stroke engines are common in handheld outdoor power tools including <a href="/wiki/Leaf_blower" title="Leaf blower">leaf blowers</a>, <a href="/wiki/Chainsaw" title="Chainsaw">chainsaws</a>, and <a href="/wiki/String_trimmer" title="String trimmer">string trimmers</a>. </p><p>Two-stroke <a href="/wiki/Diesel_engine" title="Diesel engine">diesel engines</a> are found mostly in large industrial and marine applications, as well as some trucks and heavy machinery. </p> <div class="mw-heading mw-heading2"><h2 id="Designs">Designs</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=4" title="Edit section: Designs"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Kunmadaras_Motorsport_2021._szeptember_19._JM_(69).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3f/Kunmadaras_Motorsport_2021._szeptember_19._JM_%2869%29.jpg/220px-Kunmadaras_Motorsport_2021._szeptember_19._JM_%2869%29.jpg" decoding="async" width="220" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3f/Kunmadaras_Motorsport_2021._szeptember_19._JM_%2869%29.jpg/330px-Kunmadaras_Motorsport_2021._szeptember_19._JM_%2869%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3f/Kunmadaras_Motorsport_2021._szeptember_19._JM_%2869%29.jpg/440px-Kunmadaras_Motorsport_2021._szeptember_19._JM_%2869%29.jpg 2x" data-file-width="4291" data-file-height="2861" /></a><figcaption>Two-stroke motorbike with an expansion chamber exhaust system that increases the cylinder charge</figcaption></figure> <p>Although the principles remain the same, the mechanical details of various two-stroke engines differ depending on the type. The design types vary according to the method of introducing the charge to the cylinder, the method of scavenging the <a href="/wiki/Cylinder_(engine)" title="Cylinder (engine)">cylinder</a> (exchanging burnt exhaust for fresh mixture) and the method of exhausting the cylinder. </p> <div class="mw-heading mw-heading3"><h3 id="Inlet_port_variations">Inlet port variations</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=5" title="Edit section: Inlet port variations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Piston-controlled_inlet_port">Piston-controlled inlet port</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=6" title="Edit section: Piston-controlled inlet port"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><a href="/wiki/Piston" title="Piston">Piston</a> port is the simplest of the designs and the most common in small two-stroke engines. All functions are controlled solely by the piston covering and uncovering the ports as it moves up and down in the cylinder. In the 1970s, <a href="/wiki/Yamaha_Motor_Company" title="Yamaha Motor Company">Yamaha</a> worked out some basic principles for this system. They found that, in general, widening an exhaust port increases the power by the same amount as raising the port, but the power band does not narrow as it does when the port is raised. However, a mechanical limit exists to the width of a single exhaust port, at about 62% of the bore diameter for reasonable piston ring life. Beyond this, the piston rings bulge into the exhaust port and wear quickly. A maximum 70% of bore width is possible in racing engines, where rings are changed every few races. Intake duration is between 120 and 160°. Transfer port time is set at a minimum of 26°. The strong, low-pressure pulse of a racing two-stroke expansion chamber can drop the pressure to -7 psi when the piston is at bottom dead center, and the transfer ports nearly wide open. One of the reasons for high fuel consumption in two-strokes is that some of the incoming pressurized fuel-air mixture is forced across the top of the piston, where it has a cooling action, and straight out the exhaust pipe. An <a href="/wiki/Expansion_chamber" title="Expansion chamber">expansion chamber</a> with a strong reverse pulse stops this outgoing flow.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p><p>A fundamental difference from typical four-stroke engines is that the two-stroke's <a href="/wiki/Crankcase" title="Crankcase">crankcase</a> is sealed and forms part of the induction process in gasoline and <a href="/wiki/Hot-bulb_engine" title="Hot-bulb engine">hot-bulb engines</a>. Diesel two-strokes often add a <a href="/wiki/Roots_blower" title="Roots blower">Roots blower</a> or piston pump for <a href="/wiki/Scavenging_(engine)" title="Scavenging (engine)">scavenging</a>. </p> <div class="mw-heading mw-heading4"><h4 id="Reed_inlet_valve">Reed inlet valve</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=7" title="Edit section: Reed inlet valve"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Reed_valve" title="Reed valve">Reed valve</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Old_Cox_Babe_Bee_engine_dissasembled.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Old_Cox_Babe_Bee_engine_dissasembled.JPG/220px-Old_Cox_Babe_Bee_engine_dissasembled.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Old_Cox_Babe_Bee_engine_dissasembled.JPG/330px-Old_Cox_Babe_Bee_engine_dissasembled.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Old_Cox_Babe_Bee_engine_dissasembled.JPG/440px-Old_Cox_Babe_Bee_engine_dissasembled.JPG 2x" data-file-width="2272" data-file-height="1704" /></a><figcaption>A <a href="/wiki/Cox_Models" title="Cox Models">Cox</a> Babe Bee 0.049 in<sup>3</sup> (0.80 cm<sup>3</sup>) reed valve engine, disassembled, uses glow-plug ignition. Its mass is 64 g.</figcaption></figure> <p>The reed valve is a simple but highly effective form of <a href="/wiki/Check_valve" title="Check valve">check valve</a> commonly fitted in the intake tract of the piston-controlled port. It allows asymmetric intake of the fuel charge, improving power and economy, while widening the power band. Such valves are widely used in motorcycle, ATV, and marine outboard engines. </p> <div class="mw-heading mw-heading4"><h4 id="Rotary_inlet_valve">Rotary inlet valve</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=8" title="Edit section: Rotary inlet valve"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The intake pathway is opened and closed by a rotating member. A familiar type sometimes seen on small motorcycles is a slotted disk attached to the <a href="/wiki/Crankshaft" title="Crankshaft">crankshaft</a>, which covers and uncovers an opening in the end of the crankcase, allowing charge to enter during one portion of the cycle (called a disc valve). </p><p>Another form of rotary inlet valve used on two-stroke engines employs two cylindrical members with suitable cutouts arranged to rotate one within the other - the inlet pipe having passage to the crankcase only when the two cutouts coincide. The crankshaft itself may form one of the members, as in most glow-plug model engines. In another version, the crank disc is arranged to be a close-clearance fit in the crankcase, and is provided with a cutout that lines up with an inlet passage in the crankcase wall at the appropriate time, as in <a href="/wiki/Vespa" title="Vespa">Vespa</a> motor scooters. </p><p>The advantage of a <a href="/wiki/Rotary_valve" title="Rotary valve">rotary valve</a> is that it enables the two-stroke engine's intake timing to be asymmetrical, which is not possible with piston-port type engines. The piston-port type engine's intake timing opens and closes before and after top dead center at the same crank angle, making it symmetrical, whereas the rotary valve allows the opening to begin and close earlier. </p><p>Rotary valve engines can be tailored to deliver power over a wider speed range or higher power over a narrower speed range than either a piston-port or reed-valve engine. Where a portion of the rotary valve is a portion of the crankcase itself, of particular importance, no wear should be allowed to take place. </p> <div class="mw-heading mw-heading3"><h3 id="Scavenging_variations">Scavenging variations</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=9" title="Edit section: Scavenging variations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Cross-flow_scavenging">Cross-flow scavenging</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=10" title="Edit section: Cross-flow scavenging"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Two-stroke_deflector_piston_(Autocar_Handbook,_13th_ed,_1935).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Two-stroke_deflector_piston_%28Autocar_Handbook%2C_13th_ed%2C_1935%29.jpg/170px-Two-stroke_deflector_piston_%28Autocar_Handbook%2C_13th_ed%2C_1935%29.jpg" decoding="async" width="170" height="194" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Two-stroke_deflector_piston_%28Autocar_Handbook%2C_13th_ed%2C_1935%29.jpg/255px-Two-stroke_deflector_piston_%28Autocar_Handbook%2C_13th_ed%2C_1935%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Two-stroke_deflector_piston_%28Autocar_Handbook%2C_13th_ed%2C_1935%29.jpg/340px-Two-stroke_deflector_piston_%28Autocar_Handbook%2C_13th_ed%2C_1935%29.jpg 2x" data-file-width="759" data-file-height="867" /></a><figcaption><a href="/wiki/Deflector_piston" class="mw-redirect" title="Deflector piston">Deflector piston</a> with cross-flow scavenging</figcaption></figure> <p>In a cross-flow engine, the transfer and exhaust ports are on opposite sides of the cylinder, and a <a href="/wiki/Deflector_piston" class="mw-redirect" title="Deflector piston">deflector</a> on the top of the piston directs the fresh intake charge into the upper part of the cylinder, pushing the residual <a href="/wiki/Exhaust_gas" title="Exhaust gas">exhaust gas</a> down the other side of the deflector and out the exhaust port.<sup id="cite_ref-Irving,_13_10-0" class="reference"><a href="#cite_note-Irving,_13-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> The deflector increases the piston's weight and exposed surface area, and the fact that it makes piston cooling and achieving an effective combustion chamber shape more difficult is why this design has been largely superseded by uniflow scavenging after the 1960s, especially for motorcycles, but for smaller or slower engines using direct injection, the deflector piston can still be an acceptable approach. </p> <div class="mw-heading mw-heading4"><h4 id="Loop_scavenging">Loop scavenging</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=11" title="Edit section: Loop scavenging"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Ciclo_del_motore_2T.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Ciclo_del_motore_2T.svg/290px-Ciclo_del_motore_2T.svg.png" decoding="async" width="290" height="290" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Ciclo_del_motore_2T.svg/435px-Ciclo_del_motore_2T.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Ciclo_del_motore_2T.svg/580px-Ciclo_del_motore_2T.svg.png 2x" data-file-width="400" data-file-height="400" /></a><figcaption>The two-stroke cycle <div><ol><li>Top dead center (TDC)</li><li>Bottom dead center (BDC)</li></ol></div> <style data-mw-deduplicate="TemplateStyles:r981673959">.mw-parser-output .legend{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .legend-color{display:inline-block;min-width:1.25em;height:1.25em;line-height:1.25;margin:1px 0;text-align:center;border:1px solid black;background-color:transparent;color:black}.mw-parser-output .legend-text{}</style><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#10ff00; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> A: Intake/scavenging</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r981673959"><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#639eff; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> B: Exhaust</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r981673959"><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#ffae21; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> C: Compression</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r981673959"><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#f00; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> D: Expansion (power)</div> </figcaption></figure> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Schnuerle_porting" title="Schnuerle porting">Schnuerle porting</a></div> <p>This method of scavenging uses carefully shaped and positioned transfer ports to direct the flow of fresh mixture toward the combustion chamber as it enters the cylinder. The fuel/air mixture strikes the <a href="/wiki/Cylinder_head" title="Cylinder head">cylinder head</a>, then follows the curvature of the combustion chamber, and then is deflected downward. </p><p>This not only prevents the fuel/air mixture from traveling directly out the exhaust port, but also creates a swirling turbulence which improves <a href="/wiki/Combustion_efficiency" title="Combustion efficiency">combustion efficiency</a>, power, and economy. Usually, a piston deflector is not required, so this approach has a distinct advantage over the cross-flow scheme (above). </p><p>Often referred to as "Schnuerle" (or "Schnürle") loop scavenging after Adolf Schnürle, the German inventor of an early form in the mid-1920s, it became widely adopted in Germany during the 1930s and spread further afield after <a href="/wiki/World_War_II" title="World War II">World War II</a>. </p><p>Loop scavenging is the most common type of fuel/air mixture transfer used on modern two-stroke engines. Suzuki was one of the first manufacturers outside of Europe to adopt loop-scavenged, two-stroke engines. This operational feature was used in conjunction with the expansion chamber exhaust developed by German motorcycle manufacturer, MZ, and Walter Kaaden. </p><p>Loop scavenging, disc valves, and expansion chambers worked in a highly coordinated way to significantly increase the power output of two-stroke engines, particularly from the Japanese manufacturers Suzuki, Yamaha, and Kawasaki. Suzuki and Yamaha enjoyed success in Grand Prix motorcycle racing in the 1960s due in no small way to the increased power afforded by loop scavenging. </p><p>An additional benefit of loop scavenging was the piston could be made nearly flat or slightly domed, which allowed the piston to be appreciably lighter and stronger, and consequently to tolerate higher engine speeds. The "flat top" piston also has better thermal properties and is less prone to uneven heating, expansion, piston seizures, dimensional changes, and compression losses. </p><p>SAAB built 750- and 850-cc three-cylinder engines based on a DKW design that proved reasonably successful employing loop charging. The original SAAB 92 had a two-cylinder engine of comparatively low efficiency. At cruising speed, reflected-wave, exhaust-port blocking occurred at too low a frequency. Using the asymmetrical three-port exhaust manifold employed in the identical DKW engine improved fuel economy. </p><p>The 750-cc standard engine produced 36 to 42 hp, depending on the model year. The Monte Carlo Rally variant, 750-cc (with a filled crankshaft for higher base compression), generated 65 hp. An 850-cc version was available in the 1966 SAAB Sport (a standard trim model in comparison to the deluxe trim of the Monte Carlo). Base compression comprises a portion of the overall compression ratio of a two-stroke engine. Work published at SAE in 2012 points that loop scavenging is under every circumstance more efficient than cross-flow scavenging. </p> <div class="mw-heading mw-heading4"><h4 id="Uniflow_scavenging">Uniflow scavenging</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=12" title="Edit section: Uniflow scavenging"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul class="gallery mw-gallery-packed"> <li class="gallerybox" style="width: 95.333333333333px"> <div class="thumb" style="width: 93.333333333333px;"><span typeof="mw:File"><a href="/wiki/File:Uniflow_2-stroke_diesel_animation.gif" class="mw-file-description" title="Two-stroke diesel uniflow engine animation"><img alt="Two-stroke diesel uniflow engine animation" src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Uniflow_2-stroke_diesel_animation.gif/140px-Uniflow_2-stroke_diesel_animation.gif" decoding="async" width="94" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Uniflow_2-stroke_diesel_animation.gif/211px-Uniflow_2-stroke_diesel_animation.gif 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Uniflow_2-stroke_diesel_animation.gif/281px-Uniflow_2-stroke_diesel_animation.gif 2x" data-file-width="750" data-file-height="1200" /></a></span></div> <div class="gallerytext">Two-stroke diesel uniflow engine animation</div> </li> <li class="gallerybox" style="width: 152px"> <div class="thumb" style="width: 150px;"><span typeof="mw:File"><a href="/wiki/File:Diesel_engine_uniflow.svg" class="mw-file-description" title="Uniflow scavenging flow schematic"><img alt="Uniflow scavenging flow schematic" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f7/Diesel_engine_uniflow.svg/225px-Diesel_engine_uniflow.svg.png" decoding="async" width="150" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f7/Diesel_engine_uniflow.svg/338px-Diesel_engine_uniflow.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f7/Diesel_engine_uniflow.svg/450px-Diesel_engine_uniflow.svg.png 2x" data-file-width="512" data-file-height="512" /></a></span></div> <div class="gallerytext">Uniflow scavenging flow schematic</div> </li> </ul> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Ciclo_del_motore_2T_unidirezionale.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Ciclo_del_motore_2T_unidirezionale.svg/220px-Ciclo_del_motore_2T_unidirezionale.svg.png" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Ciclo_del_motore_2T_unidirezionale.svg/330px-Ciclo_del_motore_2T_unidirezionale.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Ciclo_del_motore_2T_unidirezionale.svg/440px-Ciclo_del_motore_2T_unidirezionale.svg.png 2x" data-file-width="400" data-file-height="400" /></a><figcaption>The uniflow two-stroke cycle: <div><ol><li>Top dead center (TDC)</li><li>Bottom dead center (BDC)</li></ol></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r981673959"><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#10ff00; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> A: Intake (effective scavenging, 135°–225°; necessarily symmetric about BDC; Diesel injection is usually initiated at 4° before TDC)</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r981673959"><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#639eff; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> B: Exhaust</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r981673959"><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#ffae21; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> C: Compression</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r981673959"><div class="legend"><span class="legend-color mw-no-invert" style="background-color:#f00; color:black;-webkit-print-color-adjust: exact; print-color-adjust: exact;"> </span> D: Expansion (power)</div></figcaption></figure> <p>In a uniflow engine, the mixture, or "charge air" in the case of a diesel, enters at one end of the cylinder controlled by the piston and the exhaust exits at the other end controlled by an exhaust valve or piston. The scavenging gas-flow is, therefore, in one direction only, hence the name uniflow. </p><p>The design using exhaust valve(s) is common in on-road, off-road, and stationary two-stroke engines (<a href="/wiki/Detroit_Diesel" title="Detroit Diesel">Detroit Diesel</a>), certain small marine two-stroke engines (<a href="/wiki/Gray_Marine_Motor_Company" title="Gray Marine Motor Company">Gray Marine Motor Company</a>, which adapted the <a href="/wiki/Detroit_Diesel_Series_71" title="Detroit Diesel Series 71">Detroit Diesel Series 71</a> for <a href="/wiki/Gray_Marine_6-71_Diesel_Engine" title="Gray Marine 6-71 Diesel Engine">marine use</a>), certain railroad two-stroke <a href="/wiki/Diesel_locomotive" title="Diesel locomotive">diesel locomotives</a> (<a href="/wiki/Electro-Motive_Diesel" title="Electro-Motive Diesel">Electro-Motive Diesel</a>) and large marine two-stroke main propulsion engines (<a href="/wiki/W%C3%A4rtsil%C3%A4" title="Wärtsilä">Wärtsilä</a>). Ported types are represented by the <a href="/wiki/Opposed_piston" class="mw-redirect" title="Opposed piston">opposed piston</a> design in which two pistons are in each cylinder, working in opposite directions such as the <a href="/wiki/Junkers_Jumo_205" title="Junkers Jumo 205">Junkers Jumo 205</a> and <a href="/wiki/Napier_Deltic" title="Napier Deltic">Napier Deltic</a>.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> The once-popular <a href="/wiki/Split-single" class="mw-redirect" title="Split-single">split-single</a> design falls into this class, being effectively a folded uniflow. With advanced-angle exhaust timing, uniflow engines can be supercharged with a crankshaft-driven blower, either piston or Roots-type.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Stepped_piston_engine">Stepped piston engine</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=13" title="Edit section: Stepped piston engine"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The piston of this engine is "top-hat"-shaped; the upper section forms the regular cylinder, and the lower section performs a scavenging function. The units run in pairs, with the lower half of one piston charging an adjacent combustion chamber. </p><p>The upper section of the piston still relies on total-loss lubrication, but the other engine parts are sump lubricated with cleanliness and reliability benefits. The mass of the piston is only about 20% more than a loop-scavenged engine's piston because skirt thicknesses can be less.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Power-valve_systems">Power-valve systems</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=14" title="Edit section: Power-valve systems"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Two-stroke_power_valve_system" title="Two-stroke power valve system">Two-stroke power valve system</a></div> <p>Many modern two-stroke engines employ a <a href="/wiki/Two-stroke_power_valve_system" title="Two-stroke power valve system">power-valve system</a>. The valves are normally in or around the exhaust ports. They work in one of two ways; either they alter the exhaust port by closing off the top part of the port, which alters port timing, such as <a href="/wiki/Rotax" title="Rotax">Rotax</a> R.A.V.E, <a href="/wiki/Yamaha_Corporation" title="Yamaha Corporation">Yamaha</a> YPVS, <a href="/wiki/Honda" title="Honda">Honda</a> RC-Valve, <a href="/wiki/Kawasaki_Heavy_Industries_Motorcycle_%26_Engine" class="mw-redirect" title="Kawasaki Heavy Industries Motorcycle & Engine">Kawasaki</a> K.I.P.S., <a href="/wiki/Cagiva" title="Cagiva">Cagiva</a> C.T.S., or <a href="/wiki/Suzuki" title="Suzuki">Suzuki</a> AETC systems, or by altering the volume of the exhaust, which changes the resonant frequency of the <a href="/wiki/Expansion_chamber" title="Expansion chamber">expansion chamber</a>, such as the <a href="/wiki/Suzuki" title="Suzuki">Suzuki</a> SAEC and <a href="/wiki/Honda" title="Honda">Honda</a> V-TACS system. The result is an engine with better low-speed power without sacrificing high-speed power. However, as power valves are in the hot gas flow, they need regular maintenance to perform well. </p> <div class="mw-heading mw-heading2"><h2 id="Direct_injection">Direct injection</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=15" title="Edit section: Direct injection"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Gasoline_direct_injection#In_two-stroke_engines" title="Gasoline direct injection">Gasoline direct injection § In two-stroke engines</a></div> <p>Direct injection has considerable advantages in two-stroke engines. In carburetted two-strokes, a major problem is a portion of the fuel/air mixture going directly out, unburned, through the exhaust port, and direct injection effectively eliminates this problem. Two systems are in use: low-pressure air-assisted injection and high-pressure injection. </p><p>Since the fuel does not pass through the crankcase, a separate source of lubrication is needed. </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/API-TC" title="API-TC">API-TC</a></div> <div class="mw-heading mw-heading2"><h2 id="Two-stroke_reversibility">Two-stroke reversibility</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=16" title="Edit section: Two-stroke reversibility"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>For the purpose of this discussion, it is convenient to think in motorcycle terms, where the exhaust pipe faces into the cooling air stream, and the crankshaft commonly spins in the same axis and direction as do the wheels i.e. "forward". Some of the considerations discussed here apply to four-stroke engines (which cannot reverse their direction of rotation without considerable modification), almost all of which spin forward, too. It is also useful to note that the "front" and "back" faces of the piston are - respectively - the exhaust port and intake port sides of it, and are not to do with the top or bottom of the piston. </p><p>Regular gasoline two-stroke engines can run backward for short periods and under light load with little problem, and this has been used to provide a reversing facility in <a href="/wiki/Microcar" title="Microcar">microcars</a>, such as the <a href="/wiki/Messerschmitt_KR200" title="Messerschmitt KR200">Messerschmitt KR200</a>, that lacked reverse gearing. Where the vehicle has electric starting, the motor is turned off and restarted backward by turning the key in the opposite direction. Two-stroke <a href="/wiki/Golf_cart" title="Golf cart">golf carts</a> have used a similar system. Traditional flywheel <a href="/wiki/Ignition_magneto" title="Ignition magneto">magnetos</a> (using contact-breaker points, but no external coil) worked equally well in reverse because the cam controlling the points is symmetrical, breaking contact before <a href="/wiki/Dead_centre_(engineering)" title="Dead centre (engineering)">top dead center</a> equally well whether running forward or backward. Reed-valve engines run backward just as well as piston-controlled porting, though rotary valve engines have asymmetrical inlet timing and do not run very well. </p><p>Serious disadvantages exist for running many engines backward under load for any length of time, and some of these reasons are general, applying equally to both two-stroke and four-stroke engines. This disadvantage is accepted in most cases where cost, weight, and size are major considerations. The problem comes about because in "forward" running, the major thrust face of the piston is on the back face of the cylinder, which in a two-stroke particularly, is the coolest and best-lubricated part. The forward face of the piston in a <a href="/wiki/Trunk_engine" class="mw-redirect" title="Trunk engine">trunk engine</a> is less well-suited to be the major thrust face, since it covers and uncovers the exhaust port in the cylinder, the hottest part of the engine, where piston lubrication is at its most marginal. The front face of the piston is also more vulnerable since the exhaust port, the largest in the engine, is in the front wall of the cylinder. Piston skirts and rings risk being extruded into this port, so having them pressing hardest on the opposite wall (where there are only the transfer ports in a crossflow engine) is always best and support is good. In some engines, the <a href="/wiki/Small_end" class="mw-redirect" title="Small end">small end</a> is offset to reduce thrust in the intended rotational direction and the forward face of the piston has been made thinner and lighter to compensate, but when running backward, this weaker forward face suffers increased mechanical stress it was not designed to resist.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> This can be avoided by the use of <a href="/wiki/Crosshead" title="Crosshead">crossheads</a> and also using <a href="/wiki/Thrust_bearing" title="Thrust bearing">thrust bearings</a> to isolate the engine from end loads. </p><p>Large two-stroke ship diesels are sometimes made to be reversible. Like four-stroke ship engines (some of which are also reversible), they use mechanically operated valves, so require additional camshaft mechanisms. These engines use crossheads to eliminate sidethrust on the piston and isolate the under-piston space from the crankcase. </p><p>On top of other considerations, the oil pump of a modern two-stroke may not work in reverse, in which case the engine suffers oil starvation within a short time. Running a motorcycle engine backward is relatively easy to initiate, and in rare cases, can be triggered by a back-fire.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (June 2018)">citation needed</span></a></i>]</sup> It is not advisable. </p><p>Model airplane engines with reed valves can be mounted in either tractor or <a href="/wiki/Pusher_propeller" class="mw-redirect" title="Pusher propeller">pusher</a> configuration without needing to change the propeller. These motors are compression ignition, so no ignition timing issues and little difference between running forward and running backward are seen. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=17" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col" style="column-width: 22em;"> <ul><li><a href="/wiki/Bourke_engine" title="Bourke engine">Bourke engine</a></li> <li><a href="/wiki/Four-stroking" title="Four-stroking">Four-stroking</a></li> <li><a href="/wiki/Junkers_Jumo_205" title="Junkers Jumo 205">Junkers Jumo 205</a></li> <li><a href="/wiki/Kadenacy_effect" title="Kadenacy effect">Kadenacy effect</a></li> <li><a href="/wiki/Rolls-Royce_Crecy" title="Rolls-Royce Crecy">Rolls-Royce Crecy</a></li> <li><a href="/wiki/Pistonless_rotary_engine" title="Pistonless rotary engine">Rotary engine</a></li> <li><a href="/wiki/Twingle_engine" class="mw-redirect" title="Twingle engine">Twingle engine</a></li> <li><a href="/wiki/Stroke_(engine)" title="Stroke (engine)">Stroke (engine)</a> <ul><li><a href="/wiki/Two-_and_four-stroke_engines" title="Two- and four-stroke engines">Two- and four-stroke engines</a></li> <li><a href="/wiki/Four-stroke_engine" title="Four-stroke engine">Four-stroke engine</a></li> <li><a href="/wiki/Five-stroke_engine" title="Five-stroke engine">Five-stroke engine</a> (uncommon)</li> <li><a href="/wiki/Six-stroke_engine" title="Six-stroke engine">Six-stroke engine</a></li></ul></li> <li><a href="/wiki/W%C3%A4rtsil%C3%A4-Sulzer_RTA96-C" title="Wärtsilä-Sulzer RTA96-C">Wärtsilä-Sulzer RTA96-C</a></li> <li><a href="/wiki/Wankel_engine" title="Wankel engine">Wankel engine</a></li></ul> </div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=18" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1 cs1-prop-foreign-lang-source"><a rel="nofollow" class="external text" href="https://docker.ma/">"Docker Maroc"</a> (in French)<span class="reference-accessdate">. Retrieved <span class="nowrap">2023-04-12</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Docker+Maroc&rft_id=https%3A%2F%2Fdocker.ma%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">See: <ul><li>Clerk, Dugald; English patent no. 1,089 (issued: March 14, 1881).</li> <li>Clerk, Dugald <a rel="nofollow" class="external text" href="https://pdfpiw.uspto.gov/.piw?Docid=00249307">"Motor worked by combustible gas or vapor,"</a> U.S. patent no. 249,307 (filed: September 2, 1881; issued: November 8, 1881).</li></ul> </span></li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">See: <ul><li>Day, Joseph; British patent no. 6,410 (issued: April 14, 1891).</li> <li>Day, Joseph; British patent no. 9,247 (issued: July 1, 1891).</li> <li>Day, Joseph <a rel="nofollow" class="external text" href="https://pdfpiw.uspto.gov/.piw?docid=00543614">"Gas-engine"</a> US patent no. 543,614 (filed: May 21, 1892; issued: July 30, 1895).</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTorrens1992" class="citation journal cs1">Torrens, Hugh S. (May 1992). "A study of 'failure' with a 'successful innovation': Joseph Day and the two-stroke internal combustion engine". <i>Social Studies of Science</i>. <b>22</b> (2): <span class="nowrap">245–</span>262. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1177%2F030631292022002004">10.1177/030631292022002004</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:110285769">110285769</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Social+Studies+of+Science&rft.atitle=A+study+of+%27failure%27+with+a+%27successful+innovation%27%3A+Joseph+Day+and+the+two-stroke+internal+combustion+engine&rft.volume=22&rft.issue=2&rft.pages=%3Cspan+class%3D%22nowrap%22%3E245-%3C%2Fspan%3E262&rft.date=1992-05&rft_id=info%3Adoi%2F10.1177%2F030631292022002004&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A110285769%23id-name%3DS2CID&rft.aulast=Torrens&rft.aufirst=Hugh+S.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></li></ul> </span></li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text">Joseph Day's engine used a reed valve. One of Day's employees, Frederic Cock (1863–1944), found a way to render the engine completely valve-less. See: <ul><li>Cock, Frederic William Caswell; British patent no. 18,513 (issued: October 15, 1892).</li> <li>Cock, Frederic William Caswell <a rel="nofollow" class="external text" href="https://pdfpiw.uspto.gov/.piw?docid=00544210">"Gas-engine"</a> US patent no. 544,210 (filed: March 10, 1894; issued: August 6, 1895).</li> <li>The Day-Cock engine is illustrated in: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDowson1893" class="citation journal cs1">Dowson, Joseph Emerson (1893). <a rel="nofollow" class="external text" href="https://babel.hathitrust.org/cgi/pt?id=hvd.hxgrpu&view=1up&seq=60">"Gas-power for electric lighting: Discussion"</a>. <i>Minutes of Proceedings of the Institution of Civil Engineers</i>. <b>112</b>: <span class="nowrap">2–</span>110. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1680%2Fimotp.1893.20024">10.1680/imotp.1893.20024</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Minutes+of+Proceedings+of+the+Institution+of+Civil+Engineers&rft.atitle=Gas-power+for+electric+lighting%3A+Discussion&rft.volume=112&rft.pages=%3Cspan+class%3D%22nowrap%22%3E2-%3C%2Fspan%3E110&rft.date=1893&rft_id=info%3Adoi%2F10.1680%2Fimotp.1893.20024&rft.aulast=Dowson&rft.aufirst=Joseph+Emerson&rft_id=https%3A%2F%2Fbabel.hathitrust.org%2Fcgi%2Fpt%3Fid%3Dhvd.hxgrpu%26view%3D1up%26seq%3D60&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span>; see p. 48.</li></ul> </span></li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFClew2004" class="citation book cs1">Clew, Jeff (2004). <i>The Scott Motorcycle: The Yowling Two-Stroke</i>. Haynes Publishing. p. 240. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0854291644" title="Special:BookSources/0854291644"><bdi>0854291644</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Scott+Motorcycle%3A+The+Yowling+Two-Stroke&rft.pages=240&rft.pub=Haynes+Publishing&rft.date=2004&rft.isbn=0854291644&rft.aulast=Clew&rft.aufirst=Jeff&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.lj10.com/lj50info/">"Suzuki LJ50 INFO"</a>. Lj10.com<span class="reference-accessdate">. Retrieved <span class="nowrap">2010-11-07</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Suzuki+LJ50+INFO&rft.pub=Lj10.com&rft_id=http%3A%2F%2Fwww.lj10.com%2Flj50info%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFUS_EPA2016" class="citation web cs1">US EPA, OAR (16 August 2016). <a rel="nofollow" class="external text" href="https://www.epa.gov/vehicles-and-engines">"Vehicles and Engines"</a>. <i>US EPA</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=US+EPA&rft.atitle=Vehicles+and+Engines&rft.date=2016-08-16&rft.aulast=US+EPA&rft.aufirst=OAR&rft_id=https%3A%2F%2Fwww.epa.gov%2Fvehicles-and-engines&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20211119010136/https://motocrossactionmag.com/two-stroke-tuesday-2007-honda-cr125/">"Two-Stroke Tuesday | 2007 Honda CR125"</a>. Motocross Action magazine. 25 September 2018. Archived from <a rel="nofollow" class="external text" href="https://motocrossactionmag.com/two-stroke-tuesday-2007-honda-cr125/">the original</a> on 2021-11-19<span class="reference-accessdate">. Retrieved <span class="nowrap">2021-11-19</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Two-Stroke+Tuesday+%7C+2007+Honda+CR125&rft.pub=Motocross+Action+magazine&rft.date=2018-09-25&rft_id=https%3A%2F%2Fmotocrossactionmag.com%2Ftwo-stroke-tuesday-2007-honda-cr125%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJennings1973" class="citation book cs1">Jennings, Gordon (January 1973). "Port timing". <a rel="nofollow" class="external text" href="https://www.vintagesleds.com/library/manuals/misc/Two-stroke%20Tuner's%20Handbook.pdf"><i>Two-stroke Tuner's Handbook</i></a> <span class="cs1-format">(PDF)</span>. pp. <span class="nowrap">75–</span>90<span class="reference-accessdate">. Retrieved <span class="nowrap">14 June</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Port+timing&rft.btitle=Two-stroke+Tuner%27s+Handbook&rft.pages=%3Cspan+class%3D%22nowrap%22%3E75-%3C%2Fspan%3E90&rft.date=1973-01&rft.aulast=Jennings&rft.aufirst=Gordon&rft_id=https%3A%2F%2Fwww.vintagesleds.com%2Flibrary%2Fmanuals%2Fmisc%2FTwo-stroke%2520Tuner%27s%2520Handbook.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-Irving,_13-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-Irving,_13_10-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFIrvingTwo_stroke_power_units" class="citation book cs1"><a href="/wiki/Phil_Irving" title="Phil Irving">Irving, P.E.</a> (1967). <i>Two-Stroke Power Units</i>. Newnes. pp. <span class="nowrap">13–</span>15.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Two-Stroke+Power+Units&rft.pages=%3Cspan+class%3D%22nowrap%22%3E13-%3C%2Fspan%3E15&rft.pub=Newnes&rft.date=1967&rft.aulast=Irving&rft.aufirst=P.E.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20080501215400/http://www.iet.aau.dk/sec2/junkers.htm">"junkers"</a>. Iet.aau.dk. Archived from <a rel="nofollow" class="external text" href="http://www.iet.aau.dk/sec2/junkers.htm">the original</a> on May 1, 2008<span class="reference-accessdate">. Retrieved <span class="nowrap">2009-06-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=junkers&rft.pub=Iet.aau.dk&rft_id=http%3A%2F%2Fwww.iet.aau.dk%2Fsec2%2Fjunkers.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMcCutcheon2022" class="citation web cs1">McCutcheon, Kimble D. (1 August 2022). <a rel="nofollow" class="external text" href="https://www.enginehistory.org/Piston/Before1925/EarlyEngines/J/J.shtml">"Selected Early Engines: Junkers"</a>. <i>Engine History</i><span class="reference-accessdate">. Retrieved <span class="nowrap">14 June</span> 2024</span>. <q>Junkers built experimental two-stroke opposed-piston diesel aircraft engines during WWI, which were derived from a stationary engine line. These featured two crankshafts at the cylinder ends connected by a gear train that also drove the propeller. Two pistons, working in opposite directions in each cylinder, uncovered inlet and exhaust ports near the ends of their strokes. The exhaust port was uncovered first, and when the inlet port was uncovered, a compressed air charge was forced through the cylinders, practically clearing all burnt gases.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Engine+History&rft.atitle=Selected+Early+Engines%3A+Junkers&rft.date=2022-08-01&rft.aulast=McCutcheon&rft.aufirst=Kimble+D.&rft_id=https%3A%2F%2Fwww.enginehistory.org%2FPiston%2FBefore1925%2FEarlyEngines%2FJ%2FJ.shtml&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://airandspace.si.edu/collection-objects/junkers-jumo-207-d-v2-line-6-diesel-engine/nasm_A19660013000">"Junkers Jumo 207 D-V2 In-line 6 Diesel Engine"</a>. National Air and Space Museum<span class="reference-accessdate">. Retrieved <span class="nowrap">14 June</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Junkers+Jumo+207+D-V2+In-line+6+Diesel+Engine&rft.pub=National+Air+and+Space+Museum&rft_id=https%3A%2F%2Fairandspace.si.edu%2Fcollection-objects%2Fjunkers-jumo-207-d-v2-line-6-diesel-engine%2Fnasm_A19660013000&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://1library.net/article/stepped-piston-engines-basic-design-parameters-engine-geometry.qvvx8ngq">"Stepped-Piston Engines - BASIC DESIGN PARAMETERS 3.1 Engine and Port Geometry"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Stepped-Piston+Engines+-+BASIC+DESIGN+PARAMETERS+3.1+Engine+and+Port+Geometry&rft_id=https%3A%2F%2F1library.net%2Farticle%2Fstepped-piston-engines-basic-design-parameters-engine-geometry.qvvx8ngq&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATwo-stroke+engine" class="Z3988"></span></span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text">Ross and Ungar, "On Piston Slap as a Source of Engine Noise," ASME Paper</span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=19" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Frank Jardine (Alcoa): "Thermal Expansion in Automotive-Engine Design", SAE paper 300010</li> <li>G P Blair et al. (Univ of Belfast), R Fleck (Mercury Marine), "Predicting the Performance Characteristics of Two-Cycle Engines Fitted with Reed Induction Valves", SAE paper 790842</li> <li>G Bickle et al. (ICT Co), R Domesle et al. (Degussa AG): "Controlling Two-Stroke Engine Emissions", Automotive Engineering International (SAE) Feb 2000:27-32.</li> <li>BOSCH, "Automotive Manual", 2005, Section: Fluid's Mechanics, Table 'Discharge from High-Pressure Deposits'.</li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Two-stroke_engine&action=edit&section=20" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Commons-logo.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></a></span> Media related to <a href="https://commons.wikimedia.org/wiki/Category:Two-stroke_engines" class="extiw" title="commons:Category:Two-stroke engines">Two-stroke engines</a> at Wikimedia Commons</li> <li><a rel="nofollow" class="external text" href="http://science.howstuffworks.com/two-stroke.htm">Two-Stroke Engine</a> at <a href="/wiki/How_Stuff_Works" class="mw-redirect" title="How Stuff Works">How Stuff Works</a></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation cs2">Sherman, Don (December 17, 2009), <a rel="nofollow" class="external text" href="https://www.nytimes.com/2009/12/20/automobiles/20STROKE.html">"A Two-Stroke Revival, Without the Blue Haze"</a>, <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i></cite><span 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href="/wiki/Cornish_steam_engine" class="mw-redirect" title="Cornish steam engine">Cornish</a></li> <li><a href="/wiki/Rotative_beam_engine" class="mw-redirect" title="Rotative beam engine">Rotative</a></li></ul></li> <li><a href="/wiki/Bourke_engine" title="Bourke engine">Bourke</a></li> <li><a href="/wiki/Cam_engine" title="Cam engine">Cam engine</a></li> <li><a href="/wiki/Camless_piston_engine" title="Camless piston engine">Camless</a></li> <li><a href="/wiki/Compound_steam_engine" title="Compound steam engine">Compound</a></li> <li><a href="/wiki/Double-acting_cylinder" class="mw-redirect" title="Double-acting cylinder">Double-acting cylinder</a></li> <li><a href="/wiki/Flathead_engine" title="Flathead engine">Flathead</a></li> <li><a href="/wiki/Free-piston_engine" title="Free-piston engine">Free-piston</a> <ul><li><a href="/wiki/Stelzer_engine" title="Stelzer engine">Stelzer</a></li></ul></li> <li><a href="/wiki/Hemi_engine" class="mw-redirect" title="Hemi engine">Hemi</a></li> <li><a href="/wiki/Heron_cylinder_head" title="Heron cylinder head">Heron head</a></li> <li><a href="/wiki/IOE_engine" title="IOE engine">Intake over exhaust</a></li> <li><a href="/wiki/Oscillating_cylinder_steam_engine" title="Oscillating cylinder steam engine">Oscillating cylinder</a></li> <li><a href="/wiki/Opposed-piston_engine" title="Opposed-piston engine">Opposed-piston</a></li> <li><a href="/wiki/Overhead_camshaft_engine" title="Overhead camshaft engine">Overhead camshaft</a></li> <li><a href="/wiki/Overhead_valve_engine" title="Overhead valve engine">Overhead valve</a></li> <li><a href="/wiki/Pent-roof_combustion_chamber" title="Pent-roof combustion chamber">Pentroof</a></li> <li><a href="/wiki/Rotary_engine" title="Rotary engine">Rotary</a></li> <li><a href="/wiki/Single-acting_cylinder" class="mw-redirect" title="Single-acting cylinder">Single-acting cylinder</a></li> <li><a href="/wiki/Split_cycle_engine" class="mw-redirect" title="Split cycle engine">Split cycle</a></li> <li><a href="/wiki/Swing-piston_engine" title="Swing-piston engine">Swing-piston</a></li> <li><a href="/wiki/Uniflow_steam_engine" title="Uniflow steam engine">Uniflow</a></li> <li><a href="/wiki/Watt_steam_engine" title="Watt steam engine">Watt</a></li> <li><a href="/wiki/Chrysler_wedge_engine" class="mw-redirect" title="Chrysler wedge engine">Wedge</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Stroke_(engine)" title="Stroke (engine)">Stroke cycles</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">Two-stroke</a></li> <li><a href="/wiki/Four-stroke_engine" title="Four-stroke engine">Four-stroke</a></li> <li><a href="/wiki/Five-stroke_engine" title="Five-stroke engine">Five-stroke</a></li> <li><a href="/wiki/Six-stroke_engine" title="Six-stroke engine">Six-stroke</a></li> <li><a href="/wiki/Two-_and_four-stroke_engines" title="Two- and four-stroke engines">Two-and four-stroke</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Engine_configuration" title="Engine configuration">Cylinder layouts</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/Straight_engine" title="Straight engine">Inline / straight</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Single-cylinder_engine" title="Single-cylinder engine">I1</a></li> <li><a href="/wiki/Straight-twin_engine" title="Straight-twin engine">I2</a></li> <li><a href="/wiki/Straight-three_engine" title="Straight-three engine">I3</a></li> <li><a href="/wiki/Straight-four_engine" title="Straight-four engine">I4</a></li> <li><a href="/wiki/Straight-five_engine" title="Straight-five engine">I5</a></li> <li><a href="/wiki/Straight-six_engine" title="Straight-six engine">I6</a></li> <li><a href="/wiki/Straight-seven_engine" title="Straight-seven engine">I7</a></li> <li><a href="/wiki/Straight-eight_engine" title="Straight-eight engine">I8</a></li> <li><a href="/wiki/Straight-nine_engine" title="Straight-nine engine">I9</a></li> <li><a href="/wiki/Straight-twelve_engine" title="Straight-twelve engine">I12</a></li> <li><a href="/wiki/Straight-fourteen_engine" title="Straight-fourteen engine">I14</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/Flat_engine" title="Flat engine">Flat / boxer</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Flat-twin_engine" title="Flat-twin engine">F2</a></li> <li><a href="/wiki/Flat-four_engine" title="Flat-four engine">F4</a></li> <li><a href="/wiki/Flat-six_engine" title="Flat-six engine">F6</a></li> <li><a href="/wiki/Flat-eight_engine" title="Flat-eight engine">F8</a></li> <li><a href="/wiki/Flat-ten_engine" title="Flat-ten engine">F10</a></li> <li><a href="/wiki/Flat-twelve_engine" title="Flat-twelve engine">F12</a></li> <li><a href="/wiki/Flat-sixteen_engine" title="Flat-sixteen engine">F16</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/V_engine" title="V engine">V / Vee</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/V-twin_engine" title="V-twin engine">V2</a></li> <li><a href="/wiki/V3_engine" title="V3 engine">V3</a></li> <li><a href="/wiki/V4_engine" title="V4 engine">V4</a></li> <li><a href="/wiki/V5_engine" title="V5 engine">V5</a> <ul><li><a href="/wiki/VR5_engine" title="VR5 engine">VR5</a></li></ul></li> <li><a href="/wiki/V6_engine" title="V6 engine">V6</a> <ul><li><a href="/wiki/VR6_engine" title="VR6 engine">VR6</a></li></ul></li> <li><a href="/wiki/V8_engine" title="V8 engine">V8</a></li> <li><a href="/wiki/V10_engine" title="V10 engine">V10</a></li> <li><a href="/wiki/V12_engine" title="V12 engine">V12</a></li> <li><a href="/wiki/V14_engine" title="V14 engine">V14</a></li> <li><a href="/wiki/V16_engine" title="V16 engine">V16</a></li> <li><a href="/wiki/V18_engine" title="V18 engine">V18</a></li> <li><a href="/wiki/V20_engine" title="V20 engine">V20</a></li> <li><a href="/wiki/V24_engine" title="V24 engine">V24</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/W_engine" title="W engine">W</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/W_engine#W3_engines" title="W engine">W3</a></li> <li><a href="/wiki/W_engine#W6_engines" title="W engine">W6</a></li> <li><a href="/wiki/W8_engine" title="W8 engine">W8</a></li> <li><a href="/wiki/W12_engine" title="W12 engine">W12</a></li> <li><a href="/wiki/W16_engine" title="W16 engine">W16</a></li> <li><a href="/wiki/W18_engine" title="W18 engine">W18</a></li> <li><a href="/wiki/W_engine#W24_engine" title="W engine">W24</a></li> <li><a href="/wiki/W_engine#W30_engine" title="W engine">W30</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em">Other</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Napier_Deltic" title="Napier Deltic">Deltic</a></li> <li><a href="/wiki/H_engine" title="H engine">H</a></li> <li><a href="/wiki/Radial_engine" title="Radial engine">Radial</a></li> <li><a href="/wiki/Split-single_engine" title="Split-single engine">Split-single</a></li> <li><a href="/wiki/U_engine" title="U engine">U</a></li> <li><a href="/wiki/X_engine" title="X engine">X</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"><style data-mw-deduplicate="TemplateStyles:r886047488">.mw-parser-output .nobold{font-weight:normal}</style><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488"></div><div role="navigation" class="navbox" aria-labelledby="Car_design561" style="padding:3px"><table class="nowraplinks mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Automobile_configuration" title="Template:Automobile configuration"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Automobile_configuration" title="Template talk:Automobile configuration"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Automobile_configuration" title="Special:EditPage/Template:Automobile configuration"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Car_design561" style="font-size:114%;margin:0 4em"><a href="/wiki/Car" title="Car">Car</a> design</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Car_classification" title="Car classification">Classification</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">By size</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Microcar" title="Microcar">Micro</a></li> <li><a href="/wiki/Kei_car" title="Kei car">Kei</a></li> <li><a href="/wiki/Subcompact_car" title="Subcompact car">Subcompact</a></li> <li><a href="/wiki/B-segment" title="B-segment">Supermini</a></li> <li><a href="/wiki/Family_car" title="Family car">Family</a></li> <li><a href="/wiki/Compact_car" title="Compact car">Compact</a></li> <li><a href="/wiki/Mid-size_car" title="Mid-size car">Mid-size</a></li> <li><a href="/wiki/Full-size_car" title="Full-size car">Full-size</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Custom_car" title="Custom car">Custom</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hot_rod" title="Hot rod">Hot rod</a></li> <li><a href="/wiki/Lead_sled" title="Lead sled">Lead sled</a></li> <li><a href="/wiki/Lowrider" title="Lowrider">Lowrider</a></li> <li><a href="/wiki/Hot_rod#1960s_rise_of_the_street_rod" title="Hot rod">Street rod</a></li> <li><a href="/wiki/T-bucket" title="T-bucket">T-bucket</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Luxury_car" title="Luxury car">Luxury</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compact_executive_car" title="Compact executive car">Compact executive</a></li> <li><a href="/wiki/Executive_car" title="Executive car">Executive</a></li> <li><a href="/wiki/Personal_luxury_car" title="Personal luxury car">Personal</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Minivan" title="Minivan">Minivan / MPV</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compact_MPV" title="Compact MPV">Compact</a></li> <li><a href="/wiki/Leisure_activity_vehicle" class="mw-redirect" title="Leisure activity vehicle">Leisure</a></li> <li><a href="/wiki/Mini_MPV" title="Mini MPV">Mini</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/SUV" title="SUV">SUV</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compact_sport_utility_vehicle" title="Compact sport utility vehicle">Compact</a></li> <li><a href="/wiki/Crossover_(automobile)" title="Crossover (automobile)">Crossover (CUV)</a></li> <li><a href="/wiki/Mini_SUV" class="mw-redirect" title="Mini SUV">Mini</a></li> <li><a href="/wiki/Coupe_SUV" title="Coupe SUV">Coupe SUV</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Sports_car" title="Sports car">Sports</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Grand_tourer" title="Grand tourer">Grand tourer</a></li> <li><a href="/wiki/Hot_hatch" title="Hot hatch">Hot hatch</a></li> <li><a href="/wiki/Muscle_car" title="Muscle car">Muscle</a></li> <li><a href="/wiki/Pony_car" title="Pony car">Pony</a></li> <li><a href="/wiki/Sport_compact" title="Sport compact">Sport compact</a></li> <li><a href="/wiki/Sports_sedan" title="Sports sedan">Sports sedan</a></li> <li><a href="/wiki/Supercar" title="Supercar">Super</a></li> <li><a href="/wiki/Go-kart" title="Go-kart">Go-kart</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Antique_car" title="Antique car">Antique</a></li> <li><a href="/wiki/Classic_car" title="Classic car">Classic</a></li> <li><a href="/wiki/Economy_car" title="Economy car">Economy</a></li> <li><a href="/wiki/Ute_(vehicle)" title="Ute (vehicle)">Ute</a></li> <li><a href="/wiki/Van" title="Van">Van</a></li> <li><a href="/wiki/Vintage_car" title="Vintage car">Vintage car</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Euro_Car_Segment" title="Euro Car Segment">EU</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/A-segment" title="A-segment">A-segment</a></li> <li><a href="/wiki/B-segment" title="B-segment">B-segment</a></li> <li><a href="/wiki/C-segment" title="C-segment">C-segment</a></li> <li><a href="/wiki/D-segment" title="D-segment">D-segment</a></li> <li><a href="/wiki/E-segment" title="E-segment">E-segment</a></li> <li><a href="/wiki/F-segment" title="F-segment">F-segment</a></li> <li><a href="/wiki/J-segment" class="mw-redirect" title="J-segment">J-segment</a></li> <li><a href="/wiki/M-segment" class="mw-redirect" title="M-segment">M-segment</a></li> <li><a href="/wiki/S-segment" title="S-segment">S-segment</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Car_body_style" title="Car body style">Body styles</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/2%2B2_(car_body_style)" title="2+2 (car body style)">2+2</a></li> <li><a href="/wiki/Baquet_(car_body_style)" class="mw-redirect" title="Baquet (car body style)">Baquet</a></li> <li><a href="/wiki/Barchetta" title="Barchetta">Barchetta</a></li> <li><a href="/wiki/Berlinetta" title="Berlinetta">Berlinetta</a></li> <li><a href="/wiki/Brougham_(car_body)" title="Brougham (car body)">Brougham</a></li> <li><a href="/wiki/Cabrio_coach" title="Cabrio coach">Cabrio coach</a></li> <li><a href="/wiki/Cab_over" title="Cab over">Cab over</a></li> <li><a href="/wiki/Convertible" title="Convertible">Cabriolet / Convertible / Drophead coupe</a></li> <li><a href="/wiki/Coupe" title="Coupe">Coupe</a></li> <li><a href="/wiki/Coupe_de_Ville" class="mw-redirect" title="Coupe de Ville">Coupé de Ville / Sedanca de Ville</a></li> <li><a href="/wiki/Coup%C3%A9_utility" title="Coupé utility">Coupé utility</a></li> <li><a href="/wiki/Fastback" title="Fastback">Fastback</a></li> <li><a href="/wiki/Hardtop" title="Hardtop">Hardtop</a></li> <li><a href="/wiki/Hatchback" title="Hatchback">Hatchback</a></li> <li><a href="/wiki/Kammback" title="Kammback">Kammback</a></li> <li><a href="/wiki/Landaulet_(car)" title="Landaulet (car)">Landaulet</a></li> <li><a href="/wiki/Liftback" title="Liftback">Liftback</a></li> <li><a href="/wiki/Limousine" title="Limousine">Limousine</a></li> <li><a href="/wiki/Microvan" title="Microvan">Microvan</a></li> <li><a href="/wiki/Minibus" title="Minibus">Minibus</a></li> <li><a href="/wiki/Multi-stop_truck" title="Multi-stop truck">Multi-stop truck</a></li> <li><a href="/wiki/Notchback" title="Notchback">Notchback</a></li> <li><a href="/wiki/Panel_van" title="Panel van">Panel van</a></li> <li><a href="/wiki/Phaeton_body" title="Phaeton body">Phaeton</a></li> <li><a href="/wiki/Pickup_truck" title="Pickup truck">Pickup truck</a></li> <li><a href="/wiki/Quad_coup%C3%A9" class="mw-redirect" title="Quad coupé">Quad coupé</a></li> <li><a href="/wiki/Convertible" title="Convertible">Retractable hardtop</a></li> <li><a href="/wiki/Roadster_(automobile)" class="mw-redirect" title="Roadster (automobile)">Roadster / Spider / Spyder</a></li> <li><a href="/wiki/Runabout_(car)" title="Runabout (car)">Runabout</a></li> <li><a href="/wiki/Sedan_(automobile)" title="Sedan (automobile)">Saloon / Sedan</a></li> <li><a href="/wiki/Panel_van" title="Panel van">Sedan delivery/Panel van</a></li> <li><a href="/wiki/Shooting_brake" title="Shooting brake">Shooting brake</a></li> <li><a href="/wiki/Station_wagon" title="Station wagon">Station wagon</a></li> <li><a href="/wiki/Targa_top" title="Targa top">Targa top</a></li> <li><a href="/wiki/Torpedo_(car)" title="Torpedo (car)">Torpedo</a></li> <li><a href="/wiki/Touring_car" title="Touring car">Touring</a></li> <li><a href="/wiki/Coupe_de_Ville" class="mw-redirect" title="Coupe de Ville">Town (Coupé de Ville)</a></li> <li><a href="/wiki/T-top" title="T-top">T-top</a></li> <li><a href="/wiki/Vis-%C3%A0-vis_(carriage)" title="Vis-à-vis (carriage)">Vis-à-vis</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Specialized <br />vehicles</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/All-terrain_vehicle" title="All-terrain vehicle">All-terrain vehicle</a></li> <li><a href="/wiki/Amphibious_vehicle" title="Amphibious vehicle">Amphibious</a></li> <li><a href="/wiki/Connected_car" title="Connected car">Connected</a></li> <li><a href="/wiki/Self-driving_car" title="Self-driving car">Driverless (autonomous)</a></li> <li><a href="/wiki/Go-kart" title="Go-kart">Go-kart</a></li> <li><a href="/wiki/Gyrocar" title="Gyrocar">Gyrocar</a></li> <li><a href="/wiki/Quadracycle" title="Quadracycle">Pedal car</a></li> <li><a href="/wiki/Personal_rapid_transit" title="Personal rapid transit">Personal rapid transit</a></li> <li><a href="/wiki/Police_car" title="Police car">Police car</a></li> <li><a href="/wiki/Flying_car" title="Flying car">Flying car</a></li> <li><a href="/wiki/Taxicab" class="mw-redirect" title="Taxicab">Taxicab</a></li> <li><a href="/wiki/Tow_truck" title="Tow truck">Tow truck</a></li> <li><a href="/wiki/Voiturette" title="Voiturette">Voiturette</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Ground_propulsion" title="Ground propulsion">Propulsion</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alternative_fuel_vehicle" title="Alternative fuel vehicle">Alternative fuel</a></li> <li><a href="/wiki/Autogas" title="Autogas">Autogas</a></li> <li><a href="/wiki/Biodiesel" title="Biodiesel">Biodiesel</a></li> <li><a href="/wiki/Biofuel" title="Biofuel">Biofuel</a></li> <li><a href="/wiki/Biogasoline" title="Biogasoline">Biogasoline</a></li> <li><a href="/wiki/Biogas" title="Biogas">Biogas</a></li> <li><a href="/wiki/Compressed_natural_gas" title="Compressed natural gas">Compressed natural gas</a></li> <li><a href="/wiki/Diesel_engine" title="Diesel engine">Diesel</a></li> <li><a href="/wiki/Electric_vehicle" title="Electric vehicle">Electric</a> (<a href="/wiki/Battery_electric_vehicle" title="Battery electric vehicle">battery</a></li> <li><a href="/wiki/Neighborhood_Electric_Vehicle" title="Neighborhood Electric Vehicle">NEV</a>)</li> <li><a href="/wiki/Common_ethanol_fuel_mixtures" title="Common ethanol fuel mixtures">Ethanol</a> (<a href="/wiki/E85" title="E85">E85</a>)</li> <li><a href="/wiki/Fossil_fuel" title="Fossil fuel">Fossil fuel</a></li> <li><a href="/wiki/Fuel_cell" title="Fuel cell">Fuel cell</a></li> <li><a href="/wiki/Fuel_gas" title="Fuel gas">Fuel gas</a></li> <li><a href="/wiki/Natural_gas" title="Natural gas">Natural gas</a></li> <li><a href="/wiki/Petrol_engine" title="Petrol engine">Gasoline / petrol</a> (<a href="/wiki/Gasoline_direct_injection" title="Gasoline direct injection">direct injection</a>)</li> <li><a href="/wiki/Homogeneous_charge_compression_ignition" title="Homogeneous charge compression ignition">Homogeneous charge compression ignition</a></li> <li><a href="/wiki/Hybrid_electric_vehicle" title="Hybrid electric vehicle">Hybrid</a> (<a href="/wiki/Plug-in_hybrid" title="Plug-in hybrid">plug-in</a>)</li> <li><a href="/wiki/Hydrogen_vehicle" title="Hydrogen vehicle">Hydrogen</a></li> <li><a href="/wiki/Internal_combustion_engine" title="Internal combustion engine">Internal combustion</a></li> <li><a href="/wiki/Liquid_nitrogen_engine" title="Liquid nitrogen engine">Liquid nitrogen</a></li> <li><a href="/wiki/Liquified_petroleum_gas" class="mw-redirect" title="Liquified petroleum gas">Liquified petroleum gas</a></li> <li><a href="/wiki/Steam_car" title="Steam car">Steam</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Drive_wheel" title="Drive wheel">Drive wheels</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Front-wheel_drive" title="Front-wheel drive">Front-wheel</a></li> <li><a href="/wiki/Powertrain_layout#Rear_wheel_drive_layouts" title="Powertrain layout">Rear-wheel</a></li> <li><a href="/wiki/Two-wheel_drive" title="Two-wheel drive">Two-wheel</a></li> <li><a href="/wiki/Four-wheel_drive" title="Four-wheel drive">Four-wheel</a></li> <li><a href="/wiki/Six-wheel_drive" title="Six-wheel drive">Six-wheel</a></li> <li><a href="/wiki/Eight-wheel_drive" title="Eight-wheel drive">Eight-wheel</a></li> <li><a href="/wiki/Ten-wheel_drive" class="mw-redirect" title="Ten-wheel drive">Ten-wheel</a></li> <li><a href="/wiki/Twelve-wheel_drive" class="mw-redirect" title="Twelve-wheel drive">Twelve-wheel</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Powertrain_layout" title="Powertrain layout">Engine position</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Front-engine_design" title="Front-engine design">Front</a></li> <li><a href="/wiki/Mid-engine_design" title="Mid-engine design">Mid</a></li> <li><a href="/wiki/Rear-engine_design" title="Rear-engine design">Rear</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Powertrain_layout" title="Powertrain layout">Layout</a> <br /><span class="nobold">(engine / drive)</span></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Front-engine,_front-wheel-drive_layout" title="Front-engine, front-wheel-drive layout">Front-front</a> </li> <li> <a href="/wiki/Front-mid-engine,_front-wheel-drive_layout" title="Front-mid-engine, front-wheel-drive layout">Front mid-front</a> </li> <li> <a href="/wiki/Rear-engine,_front-wheel-drive_layout" title="Rear-engine, front-wheel-drive layout">Rear-front</a> </li> <li> <a href="/wiki/Front-engine,_rear-wheel-drive_layout" title="Front-engine, rear-wheel-drive layout">Front-rear</a> </li> <li> <a href="/wiki/Rear_mid-engine,_rear-wheel-drive_layout" title="Rear mid-engine, rear-wheel-drive layout">Rear mid-rear</a> </li> <li> <a href="/wiki/Rear-engine,_rear-wheel-drive_layout" title="Rear-engine, rear-wheel-drive layout">Rear-rear</a> </li> <li> <a href="/wiki/Front-engine,_four-wheel-drive_layout" title="Front-engine, four-wheel-drive layout">Front-four-wheel</a> </li> <li> <a href="/wiki/Mid-engine,_four-wheel-drive_layout" title="Mid-engine, four-wheel-drive layout">Mid-four-wheel</a> </li> <li> <a href="/wiki/Rear-engine,_four-wheel-drive_layout" title="Rear-engine, four-wheel-drive layout">Rear-four-wheel</a> </li> <li> <a href="/wiki/Dual-motor,_four-wheel-drive_layout" title="Dual-motor, four-wheel-drive layout">Dual motor-four-wheel</a> </li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Engine_configuration" title="Engine configuration">Engine configuration</a><br /><span class="nobold">(<a href="/wiki/Internal_combustion_engine" title="Internal combustion engine">internal combustion</a>)</span></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Flat_engine" title="Flat engine">Boxer</a></li> <li><a href="/wiki/Flat_engine" title="Flat engine">Flat</a></li> <li><a href="/wiki/Four-stroke_engine" title="Four-stroke engine">Four-stroke</a></li> <li><a href="/wiki/H_engine" title="H engine">H-block</a></li> <li><a href="/wiki/Reciprocating_engine" title="Reciprocating engine">Reciprocating</a></li> <li><a href="/wiki/Single-cylinder_engine" title="Single-cylinder engine">Single-cylinder</a></li> <li><a href="/wiki/Straight_engine" title="Straight engine">Straight</a></li> <li><a class="mw-selflink selflink">Two-stroke</a></li> <li><a href="/wiki/V_engine" title="V engine">V (Vee)</a></li> <li><a href="/wiki/W_engine" title="W engine">W engine</a></li> <li><a href="/wiki/Wankel_engine" title="Wankel engine">Wankel</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="2" style="font-weight:bold;"><div> <ul><li><a href="/wiki/Portal:Cars" title="Portal:Cars">Portal</a></li> <li><a href="/wiki/Category:Cars" title="Category:Cars">Category</a></li> <li><a href="/wiki/Template:EC_car_classification" title="Template:EC car classification">Template:EC car classification</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Aircraft_piston_engine_components,_systems_and_terminology309" style="padding:3px"><table class="nowraplinks mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Aircraft_piston_engine_components" title="Template:Aircraft piston engine components"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Aircraft_piston_engine_components" title="Template talk:Aircraft piston engine components"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Aircraft_piston_engine_components" title="Special:EditPage/Template:Aircraft piston engine components"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Aircraft_piston_engine_components,_systems_and_terminology309" style="font-size:114%;margin:0 4em"><a href="/wiki/Aircraft_engine" title="Aircraft engine">Aircraft</a> <a href="/wiki/Reciprocating_engine" title="Reciprocating engine">piston engine</a> components, systems and terminology</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Reciprocating_engine" title="Reciprocating engine">Piston engines</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Mechanical<br />components</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Camshaft" title="Camshaft">Camshaft</a></li> <li><a href="/wiki/Connecting_rod" title="Connecting rod">Connecting rod</a></li> <li><a href="/wiki/Crankpin" title="Crankpin">Crankpin</a></li> <li><a href="/wiki/Crankshaft" title="Crankshaft">Crankshaft</a></li> <li><a href="/wiki/Cylinder_(engine)" title="Cylinder (engine)">Cylinder</a></li> <li><a href="/wiki/Cylinder_head" title="Cylinder head">Cylinder head</a></li> <li><a href="/wiki/Gudgeon_pin" title="Gudgeon pin">Gudgeon pin</a></li> <li><a href="/wiki/Hydraulic_tappet" title="Hydraulic tappet">Hydraulic tappet</a></li> <li><a href="/wiki/Main_bearing" title="Main bearing">Main bearing</a></li> <li><a href="/wiki/Obturator_ring" title="Obturator ring">Obturator ring</a></li> <li><a href="/wiki/Oil_pump_(internal_combustion_engine)" title="Oil pump (internal combustion engine)">Oil pump</a></li> <li><a href="/wiki/Piston" title="Piston">Piston</a></li> <li><a href="/wiki/Piston_ring" title="Piston ring">Piston ring</a></li> <li><a href="/wiki/Poppet_valve" title="Poppet valve">Poppet valve</a></li> <li><a href="/wiki/Overhead_valve_engine" title="Overhead valve engine">Pushrod</a></li> <li><a href="/wiki/Rocker_arm" title="Rocker arm">Rocker arm</a></li> <li><a href="/wiki/Sleeve_valve" title="Sleeve valve">Sleeve valve</a></li> <li><a href="/wiki/Tappet" title="Tappet">Tappet</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Electrical<br />components</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alternator_(automotive)" title="Alternator (automotive)">Alternator</a></li> <li><a href="/wiki/Capacitor_discharge_ignition" title="Capacitor discharge ignition">Capacitor discharge ignition</a></li> <li><a href="/wiki/Dual_ignition" title="Dual ignition">Dual ignition</a></li> <li><a href="/wiki/Fuel_injection" title="Fuel injection">Electronic fuel injection</a></li> <li><a href="/wiki/Electric_generator" title="Electric generator">Generator</a></li> <li><a href="/wiki/Ignition_system" title="Ignition system">Ignition system</a></li> <li><a href="/wiki/Ignition_magneto" title="Ignition magneto">Magneto</a></li> <li><a href="/wiki/Spark_plug" title="Spark plug">Spark plug</a></li> <li><a href="/wiki/Starter_(engine)" title="Starter (engine)">Starter</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Terminology</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Air-cooled_engine" title="Air-cooled engine">Air-cooled</a></li> <li><a href="/wiki/Aircraft_engine_starting" title="Aircraft engine starting">Aircraft engine starting</a></li> <li><a href="/wiki/Bore_(engine)" title="Bore (engine)">Bore</a></li> <li><a href="/wiki/Compression_ratio" title="Compression ratio">Compression ratio</a></li> <li><a href="/wiki/Dead_centre_(engineering)" title="Dead centre (engineering)">Dead centre</a></li> <li><a href="/wiki/Engine_displacement" title="Engine displacement">Engine displacement</a></li> <li><a href="/wiki/Four-stroke_engine" title="Four-stroke engine">Four-stroke engine</a></li> <li><a href="/wiki/Horsepower" title="Horsepower">Horsepower</a></li> <li><a href="/wiki/Ignition_timing" title="Ignition timing">Ignition timing</a></li> <li><a href="/wiki/Manifold_vacuum" title="Manifold vacuum">Manifold pressure</a></li> <li><a href="/wiki/Mean_effective_pressure" title="Mean effective pressure">Mean effective pressure</a></li> <li><a href="/wiki/Naturally_aspirated_engine" title="Naturally aspirated engine">Naturally aspirated</a></li> <li><a href="/wiki/Gnome_Monosoupape" title="Gnome Monosoupape">Monosoupape</a></li> <li><a href="/wiki/Overhead_camshaft" class="mw-redirect" title="Overhead camshaft">Overhead camshaft</a></li> <li><a href="/wiki/Overhead_valve_engine" title="Overhead valve engine">Overhead valve engine</a></li> <li><a href="/wiki/Rotary_engine" title="Rotary engine">Rotary engine</a></li> <li><a href="/wiki/Shock_cooling" title="Shock cooling">Shock cooling</a></li> <li><a href="/wiki/Stroke_(engine)" title="Stroke (engine)">Stroke</a></li> <li><a href="/wiki/Time_between_overhauls" title="Time between overhauls">Time between overhauls</a></li> <li><a class="mw-selflink selflink">Two-stroke engine</a></li> <li><a href="/wiki/Valve_timing" title="Valve timing">Valve timing</a></li> <li><a href="/wiki/Volumetric_efficiency" title="Volumetric efficiency">Volumetric efficiency</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Propeller_(aeronautics)" title="Propeller (aeronautics)">Propellers</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Components</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Propeller_governor" class="mw-redirect" title="Propeller governor">Propeller governor</a></li> <li><a href="/wiki/Propeller_speed_reduction_unit" title="Propeller speed reduction unit">Propeller speed reduction unit</a></li> <li><a href="/wiki/Spinner_(aeronautics)" title="Spinner (aeronautics)">Spinner</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Terminology</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Autofeather" title="Autofeather">Autofeather</a></li> <li><a href="/wiki/Blade_pitch" title="Blade pitch">Blade pitch</a></li> <li><a href="/wiki/Constant-speed_propeller" class="mw-redirect" title="Constant-speed propeller">Constant-speed</a></li> <li><a href="/wiki/Contra-rotating_propellers" title="Contra-rotating propellers">Contra-rotating</a></li> <li><a href="/wiki/Counter-rotating_propellers" title="Counter-rotating propellers">Counter-rotating</a></li> <li><a href="/wiki/Scimitar_propeller" title="Scimitar propeller">Scimitar</a></li> <li><a href="/wiki/Single-blade_propeller" title="Single-blade propeller">Single-blade</a></li> <li><a href="/wiki/Variable-pitch_propeller_(aeronautics)" title="Variable-pitch propeller (aeronautics)">Variable-pitch</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Engine instruments</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Annunciator_panel" title="Annunciator panel">Annunciator panel</a></li> <li><a href="/wiki/Electronic_flight_instrument_system" title="Electronic flight instrument system">EFIS</a></li> <li><a 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href="/wiki/Aircraft_fuel_system" title="Aircraft fuel system">Fuel</a> and induction<br />system</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Avgas" title="Avgas">Avgas</a></li> <li><a href="/wiki/Carburetor" title="Carburetor">Carburetor</a></li> <li><a href="/wiki/Fuel_injection" title="Fuel injection">Fuel injection</a></li> <li><a href="/wiki/Gascolator" title="Gascolator">Gascolator</a></li> <li><a href="/wiki/Inlet_manifold" title="Inlet manifold">Inlet manifold</a></li> <li><a href="/wiki/Intercooler" title="Intercooler">Intercooler</a></li> <li><a href="/wiki/Pressure_carburetor" title="Pressure carburetor">Pressure carburetor</a></li> <li><a href="/wiki/Supercharger" title="Supercharger">Supercharger</a></li> <li><a href="/wiki/Turbocharger" title="Turbocharger">Turbocharger</a></li> <li><a href="/wiki/Updraft_carburetor" title="Updraft carburetor">Updraft 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