Product DescriptionCentrifugal Clutch 3/4″ Bore #40/41/420 Chain 10 Tooth Go Kart Mini Bike Drift TrikeKnow your gear ratio! An acceptable gear ratio for a 12T #35 clutch would be a 60T or larger rear sprocket. A 10T #41 clutch would need a 50T or larger rear sprocket. Vehicles with rims larger than 6″ or tires with a diameter of 15″ or larger should upgrade to a belt drive TAV system. Gear ratios outside of these recommendations voids any warranty.Clutch:Shaft size: 3/4″ BoreChain Size: 40/41/420 ChainTooth Count: 12 ToothEngagement is Approximately: 1800-2200 RPMsReplace your worn our clutch with this affordable item. Can be mounted inboard or outboard. Has key stock. Does not come with set screws. Fits the following motors and many others:Honda GX160 Honda GX200Harbor Freight Greyhound 196ccHarbor Freight Predator 212ccNearly all 5.5 HP clones Nearly all 6.5 HP clonesNearly all 4-7HP motors, all brands.PLEASE MEASURE YOUR CRANKSHAFT TO BE SURE!