The crankshaft is the heart and soul of your engine - Only use the best quality for maximum performance and reliability.MALOSSI Pro Race Premium Quality for Malossi 90cc Testa Rosa Cylinder Kit or Malossi 90cc Team (Requires install kit see below)Uses 13x17 Wrist Pin BearingReinforced variator side shaft for increased strength & reliabilityUses Malossi over range variator kit 5114744Shaft is hybrid of 16mm non splined from crank bearing - about 1/2" from tip it becomes splined at 13mmTECH: 42.3mm Stroke - 90mm RodThis crank can be used with Malossi cylinder 3116919 with a 5mm spacer 0716344 and 12x17mm Wrist Pin Bearing 6611785BTECH INFO86cc Malossi 44mm Stroke x 85mm Rod - 50mm Piston Bore90cc Malossi 42.3mm Stroke x 90mm Rod - 52mm 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