mike; that assembly acts as a shock dampener or cush drive. most every chain or belt driven bike has some sort of cush drive either in the clutch pack area or rear wheel hub. the device you are describing is to cushion and dampen some of the shock-load generated in the driveline and dampen what gets delivered to the belt. for smoothness, rideability, and component longevityCan anyone shed some light on the purpose of the springs that are in the back of the clutch drum.