{"product_id":"47mm-gy6-50cc-139qmb-cylinder-kit","title":"47mm GY6 50cc (139QMB) Cylinder Kit","description":"\u003ch2\u003e47mm Cylinder Kit for 139QMB 50cc Engines\u003c\/h2\u003e\u003cp\u003eThis cylinder kit is built to take a 50cc QMB139 engine up to 72cc. Everything needed for the install is in the box, so it suits anyone wanting a more responsive scooter engine. It is one of the \u003ca href=\"\/collections\/gy6-50cc-parts\"\u003eGY6 50cc scooter parts\u003c\/a\u003e that can noticeably improve acceleration and how the engine responds overall. Note that the engine case may need modifying to make room for the larger cylinder.\u003c\/p\u003e\u003ch3\u003eWhat's in the Box\u003c\/h3\u003e\u003cp\u003eThe package includes a cylinder, piston, piston rings, piston pin, circlips, a head gasket and a base gasket. Together these parts are meant to deliver dependable running once fitted. Each piece is sized to sit properly inside the engine, so the upgrade is a fairly direct process for scooter enthusiasts.\u003c\/p\u003e\u003ch3\u003ePerformance and Specifications\u003c\/h3\u003e\u003cp\u003eThe cylinder has a 47mm bore and a sleeve outer diameter of 52.7mm. The wrist pin measures 13mm across, and the overall piston height is 34.4mm. The compression height, measured from the centre of the wrist pin hole to the top edge of the piston, is 17.25mm. These dimensions are what produce the larger displacement and the performance gain.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCylinder Bore:\u003c\/strong\u003e 47mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWrist Pin Diameter:\u003c\/strong\u003e 13mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTotal Piston Height:\u003c\/strong\u003e 34.4mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompression Height:\u003c\/strong\u003e 17.25mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncluded Components:\u003c\/strong\u003e Cylinder, piston, rings, piston pin, circlips, head gasket, base gasket\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFits:\u003c\/strong\u003e 139QMB-based 50cc engines (GY6-style, 139QMA\/QMB family) for 47mm big bore upgrade to 72cc\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eCompatible with:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e139QMA\u003c\/li\u003e\n\u003cli\u003e139QMB\u003c\/li\u003e\n\u003cli\u003e1P39QMB\u003c\/li\u003e\n\u003cli\u003e1P39QMA-2\u003c\/li\u003e\n\u003cli\u003eYN139QMB\u003c\/li\u003e\n\u003cli\u003eJJ1P39QMB\u003c\/li\u003e\n\u003cli\u003e139FMA-2\u003c\/li\u003e\n\u003cli\u003eBD1P39QMB\u003c\/li\u003e\n\u003cli\u003eBN139QMB\u003c\/li\u003e\n\u003cli\u003e147QMD\u003c\/li\u003e\n\u003cli\u003eOther QMA models\u003c\/li\u003e\n\u003cli\u003eOther QMB models\u003c\/li\u003e\n\u003cli\u003eAny engine code containing \"QM\" or \"FM\"\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eHow to choose:\u003c\/strong\u003e Check that your engine code appears on the list above. The engine case may need modification to accept the larger 52.7mm sleeve.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eBrowse further:\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-kits\"\u003eScooter Big Bore \u0026amp; Cylinder Kits\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":51134444568633,"sku":"TT-15710","price":57.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0665\/3358\/9049\/files\/47mm-gy6-50cc-139qmb-cylinder-kit-1.jpg?v=1794344016","url":"https:\/\/www.trendtimes.com\/products\/47mm-gy6-50cc-139qmb-cylinder-kit","provider":"Trend Times Toy Stores","version":"1.0","type":"link"}