US Patent 7810624 Centrifugal clutch with expansion ring assembly

A centrifugal clutch for utilization with an engine of a motorcycle is disclosed herein. The centrifugal clutch includes a clutch basket, a cover plate, a hub, first clutch plates, second clutch plates and a dynamic expansion ring assembly having cam members. The dynamic expansion ring assembly imparts substantially equal expansion forces in opposite directions. A gap is present when the engine is at an idle speed and cam members are positioned radially inward, and the gap is not present when the engine is operating faster than idle and the cam members are positioned radially outward by centrifugal force.