from another forum ............................. https://kushsprockets.3dcartstores.com/Design_ep_41.html Design Kush® sprockets were built to dampen the drive-train of Enduro, Supermoto/ Motard and other dirt bikes ridden on road(without a cushioning hub), by dampening inside the rear sprocket. To achieve this, they use an outer ring which is dampened from the inside plate by a set of polyurethane dampeners. This has been shown to give longer gear life, with the added benefit of less chain/sprocket wear and less wheel hop during compression braking. Kush sprockets are Australian engineer designed and tested. They use nitride hardened SCr440 alloy steel teeth and a 7075 aluminium carrier. To allow the outer toothed ring to rotate freely, ball bearings are housed between forged/sealed bearing races and the outer ring. Their rotation is cushioned by high performance polyurethane dampeners, providing high-cycle endurance and low compression set. They are designed to withstand a torque of 900 NM. Kush sprockets are garanteed against manufacturing faults or defects for the life of the sprocket.