Complete 70cc Racing Cylinder Big Bore Kit with 10mm Piston Pin for Yamaha JOG Zuma 2 Stroke 50cc Scooter Minarelli 1E40QMB Engine High quality complete cylinder big bore kit, includes all gaskets and components necessary to upgrade your cylinder Upgrade your engine to 70cc!! Only fit 2 stroke Yamaha Jog 50 and its clone engine Piston diameter: 47mm; Wrist pin diameter: 10mm (not for 12mm ones)