{"product_id":"gy6-50cc-139qmb-non-emissions-head-69mm-valves","title":"GY6 50cc (139QMB) Non Emissions Head - 69mm Valves","description":"\u003ch2\u003eNon-Emissions Cylinder Head for GY6 50cc and 80cc Engines\u003c\/h2\u003e\u003cp\u003eThis non-emissions head suits GY6 50cc and 80cc engines, specifically the 139QMB and 139QMA models. It is a practical replacement for owners who want to keep or raise the performance of their off-road scooters. Listed among \u003ca href=\"\/collections\/gy6-50cc-parts\"\u003eGY6 50cc scooter parts\u003c\/a\u003e, it arrives fully assembled, so fitting it is simple. Whether you are swapping out a worn component or upgrading your engine, this part is made to handle the job.\u003c\/p\u003e\u003ch3\u003eConstruction and Features\u003c\/h3\u003e\u003cp\u003eThe cylinder head uses a 4-bolt deck pattern and includes valves measuring 69mm in length. Because it has no secondary air port, it is intended for non-emissions setups. The intake port measures 17mm across and the exhaust port 18mm, which supports steady airflow during engine operation.\u003c\/p\u003e\u003ch3\u003eInstallation and Replacement\u003c\/h3\u003e\u003cp\u003eValves, springs, and retainers come already fitted, which cuts down on the work involved in replacing the head. It bolts onto compatible engines without requiring extra modifications. If you notice problems such as lost power or louder engine running, a replacement may be needed.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eEngine Type:\u003c\/strong\u003e 139QMB \/ 139QMA 4-stroke 50cc \/ 80cc\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStyle:\u003c\/strong\u003e Non-emissions (no secondary air port)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCondition:\u003c\/strong\u003e Fully assembled\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve Length:\u003c\/strong\u003e 69mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve Center-to-Center Spacing:\u003c\/strong\u003e 70.5mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntake Port Diameter:\u003c\/strong\u003e 17mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExhaust Port Diameter:\u003c\/strong\u003e 18mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeck Pattern:\u003c\/strong\u003e 4-bolt\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFits:\u003c\/strong\u003e GY6 139QMB\/139QMA 50cc and 80cc 4-stroke engines (non-emissions, no secondary air port)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eFits:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e139QMA engines (non-emissions)\u003c\/li\u003e\n\u003cli\u003e139QMB engines (non-emissions)\u003c\/li\u003e\n\u003cli\u003e1P39QMB and 1P39QMA-2 engines\u003c\/li\u003e\n\u003cli\u003eYN139QMB, JJ1P39QMB, BD1P39QMB and BN139QMB engines\u003c\/li\u003e\n\u003cli\u003e139FMA-2 engines\u003c\/li\u003e\n\u003cli\u003e147QMD engines\u003c\/li\u003e\n\u003cli\u003eOther QMA and QMB models (non-emissions)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eHow to choose:\u003c\/strong\u003e Compare your engine code with the list (stamped on the engine case) and confirm your engine has no secondary air port before you order.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eShop more:\u003c\/strong\u003e \u003ca href=\"\/collections\/gy6-50cc-parts\"\u003eGY6 50cc Scooter Parts (139QMB)\u003c\/a\u003e · \u003ca href=\"\/collections\/gy6-scooter-parts\"\u003eGY6 Scooter Parts\u003c\/a\u003e · \u003ca href=\"\/collections\/scooter-cylinder-heads\"\u003eScooter Cylinder Heads \u0026amp; Valves\u003c\/a\u003e · \u003ca href=\"\/collections\/scooter-parts\"\u003eScooter Parts\u003c\/a\u003e\u003c\/p\u003e","brand":"Trend Times Toy Stores","offers":[{"title":"Default Title","offer_id":51134442602553,"sku":"TT-15691","price":49.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0665\/3358\/9049\/files\/gy6-50cc-139qmb-non-emissions-head-69mm-valves-1.jpg?v=1794343986","url":"https:\/\/www.trendtimes.com\/products\/gy6-50cc-139qmb-non-emissions-head-69mm-valves","provider":"Trend Times Toy Stores","version":"1.0","type":"link"}