{"product_id":"gy6-50cc-139qmb-cylinder-kit-4t-81cc-iron-50mm","title":"GY6 50cc (139QMB) Cylinder Kit 4T (81cc, Iron, 50mm)","description":"\u003ch2\u003eGY6 50cc Cylinder Kit for 4-Stroke Scooters\u003c\/h2\u003e\u003cp\u003eThis cylinder kit suits the GY6 50cc (139QMB) and has a 50mm bore, built for 4-stroke scooters. Fitted to the engine, it raises displacement to 81cc and noticeably boosts performance. It belongs to our range of \u003ca href=\"\/collections\/gy6-50cc-parts\"\u003eGY6 50cc scooter parts\u003c\/a\u003e that can change how your scooter rides. For the best outcome, pair it with a compatible big valve head and a performance camshaft.\u003c\/p\u003e\u003ch3\u003ePerformance Boost\u003c\/h3\u003e\u003cp\u003eThis cast iron cylinder kit is an effective upgrade for GY6 50\/139QMB engines. It bolts straight on in place of the original cylinder, so it is a simple option for anyone wanting more speed and acceleration. With additional performance parts fitted, riders can expect top speeds of roughly 50-55 MPH.\u003c\/p\u003e\u003ch3\u003eRecommended Upgrades\u003c\/h3\u003e\u003cp\u003eTo get the most power, fit part number 1100-1239, a 50mm big valve head, since stock heads may not be compatible. The 1100-1250 performance camshaft is another worthwhile addition that works with the cylinder kit to help you make the most of your scooter.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Cast Iron\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 50mm Bore\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePosition:\u003c\/strong\u003e Cylinder Kit\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFits:\u003c\/strong\u003e CSC Go Max with the 139QMB 50cc four-stroke engine (converted from 50cc to 81cc)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eFits:\u003c\/p\u003e\u003cul\u003e\u003cli\u003eCSC Go Max (139QMB 50cc four-stroke, 50mm bore)\u003c\/li\u003e\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eHow to choose:\u003c\/strong\u003e Only use this kit on a 139QMB \/ QMB139 (GY6 50) four-stroke engine that is still in its original 50cc configuration.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhere it goes:\u003c\/strong\u003e It is part #13 on the cylinder crankshaft diagram for the CSC Go Max.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eOther versions:\u003c\/strong\u003e For the 88cc 52mm big bore kit for GY6 50 139QMB, see \u003ca href=\"\/products\/88cc-big-bore-kit-52mm-50cc-139qmb-gy6-50\"\u003e88cc Big Bore Kit (52mm) - 50cc (139QMB) \/ GY6 50\u003c\/a\u003e. For the 72cc kit with head and 64mm valves for the 139QMB, see \u003ca href=\"\/products\/gy6-50cc-139qmb-big-bore-kit-with-head-4t-72cc-64mm-valves\"\u003eGY6 50cc (139QMB) Big Bore Kit with Head 4T (72cc, 64mm Valves)\u003c\/a\u003e.\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-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":51137666383929,"sku":"TT-22723","price":125.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0665\/3358\/9049\/files\/cylinder-kit-4t-81cc-iron-50mm-for-gy6-50cc-139qmb-1.jpg?v=1794366497","url":"https:\/\/www.trendtimes.com\/products\/gy6-50cc-139qmb-cylinder-kit-4t-81cc-iron-50mm","provider":"Trend Times Toy Stores","version":"1.0","type":"link"}