The crankshaft is the heart and soul of your engine - Only use the best quality for maximum performance and reliability.2FAST Pro Race Premium Quality for 2FAST 89.9cc Cylinder KitUses 13x17 Wrist Pin BearingUses Malossi over range variator kit 5112800TECH: 45.8mm Stroke - 90mm RodTECH INFO86cc Malossi 44mm Stroke x 85mm Rod - 50mm Piston Bore86cc 2FAST 44mm Stroke x 90mm Rod - 50mm Piston Bore90cc 2FAST 45.8mm Stroke x 90mm Rod - 50mm Piston Bore94cc 2FAST 44mm Stroke x 90mm Rod - 52mm Piston Bore