{"product_id":"ncy-performance-cylinder-head-50mm-81cc-alloy-qmb139-1100-1239","title":"NCY Performance Cylinder Head (50mm, 81cc, Alloy); 139QMB","description":"\u003cp\u003eThis NCY 81cc Aluminum Performance Cylinder Head is compatible with 50cc 139QMB engines. Use this cylinder head with NCY's \u003ca title=\"ncy 81cc cylinder kit\" href=\"https:\/\/www.scooterworks.com\/products\/ncy-cylinder-kit-81cc-iron-50mm-qmb139?variant=46756515414296\"\u003e81mm Cylinder Kit\u003c\/a\u003e to give your bike the power to handle today's city traffic.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eSpecifications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eCylinder Head Stud Space: 50mm \/ H: 60mm \/ Intake Port: 24mm \/ Exhaust Port: 22mm\u003c\/li\u003e\n\u003cli\u003eValves: 21.5x64mm Intake \/ 19x64mm Exhaust \/ Stem: 5mm \/ (w\/intake valves) H: 66.1\u0026lt;67.3mm\u003c\/li\u003e\n\u003cli\u003eValve stem length: 64mm\u003c\/li\u003e\n\u003cli\u003e6mm Intake Threads\u003c\/li\u003e\n\u003cli\u003e6mm Exhaust Threads\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong style=\"font-size: 0.875rem;\"\u003eNOTE: \u003c\/strong\u003e\u003cspan style=\"font-size: 0.875rem;\"\u003eMost 139QMB stock cylinder heads have valves that are 69mm high and use a 69mm rocker arm. This cylinder head has 64mm high valves and will only work with a \u003ca href=\"https:\/\/www.scooterworks.com\/products\/rocker-arm-assembly-type-1-64mm-qmb139\" title=\"64mm rocker arm assembly GY6\"\u003e64mm rocker arm\u003c\/a\u003e. \u003c\/span\u003e\u003cspan style=\"font-size: 0.875rem;\"\u003ePlease check the stock valve stem height before ordering.\u003c\/span\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003e139QMB-based 50cc \/ 80cc engines with the following engine codes:\u003c\/strong\u003e\u003c\/p\u003e\u003ctable width=\"463\" height=\"100\" style=\"width: 87.0908%;\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003e139QMA\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003e139QMB\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003e1P39QMB\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003e1P39QMA-2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003eYN139QMB\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003eJJ1P39QMB\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003e139FMA-2\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003eBD1P39QMB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003eBN139QMB\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003e147QMD\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003eOther QMA models\u003c\/td\u003e\n\u003ctd style=\"width: 24.6905%;\"\u003eOther QMB models\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003cp\u003e\u003cspan style=\"font-size: 0.875rem;\"\u003eDon't see your engine listed? If the engine code includes \"QM\" or \"FM\" and you've ensured the valve height and rocker arm on your bike are 64mm, this product is compatible with your vehicle.\u003c\/span\u003e\u003c\/p\u003e\u003cp class=\"MsoNormal\"\u003e\u003cstrong\u003eAbout NCY:\u003c\/strong\u003e NCY is the aftermarket performance parts leader for most popular scooter brands including Honda, Yamaha, Genuine, Vespa, SYM, Lance, KYMCO, and GY6 \/ QMB powered scooters. Made in Taiwan with strict quality standards since 1997, NCY is ISO 9001 certified.\u003c\/p\u003e\u003cp class=\"MsoNormal\"\u003eMade in Taiwan.\u003c\/p\u003e\u003ch4 style=\"color: #983d3c;\"\u003eThis product is intended for off-road use only.\u003c\/h4\u003e\u003ch4 style=\"color: #983d3c;\"\u003eThis product is not intended for use on public roads or land.\u003c\/h4\u003e\u003ch4 style=\"color: #983d3c;\"\u003eThis product is not legal for use in California on pollution-controlled vehicles. Check local laws before installing.\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003e*Performance upgrades are considered racing parts and are not covered by warranty.\u003c\/strong\u003e\u003c\/p\u003e","brand":"NCY","offers":[{"title":"Default Title","offer_id":46756516069656,"sku":"1100-1239","price":168.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0782\/1728\/1816\/products\/1100-1239_1ec7c4bb-e27f-496a-b8f3-7cd1c594c333.jpg?v=1695268827","url":"https:\/\/www.scooterworks.com\/products\/ncy-performance-cylinder-head-50mm-81cc-alloy-qmb139-1100-1239","provider":"Scooterworks USA, LLC","version":"1.0","type":"link"}