For the largest stocks of mini bike clutch accessories, check the wide-ranging options at OMB Warehouse, all of the highest quality and international standards. One of the top selling items in mini bike clutch accessories and clutches that is offered as a combo is the Homgrace 10T Go Kart Mini Bike Clutch, 3/4 Bore 40/41/420 Chain Clutch Centrifugal for Go Kart Mini-Bike (Centrifugal Clutch with Chain). Specifications include 3' of #420 chain included with master link. Centrifugal Clutch 10 tooth, 3/4" bore, #40/41/420 chain with 3/16 key built in. It has a Common clutch for 3.5-7hp engines using the #40/41/420 chain. Mounts onto crankshaft using bolt and washer on the end of the crankshaft. Does not have set screws. If you need a clutch with set screws order the Max-Torque brand clutch. A keyhole on the clutch and the sike of the clutch hole are small to fit. The combo is important as accessories are very important for the overall performance of the clutch. The chain is an important accessory of the clutch. A worn-out chain will stretch, causing the rollers to ride on top of the teeth of the chain. At this point, you will prematurely wear down the teeth of the clutch as well as your drive sprocket.