Abstract: An automatic decompression mechanism for selectively actuating a cylinder valve of an engine so as to reduce the starting force required to start the engine. The mechanism includes a cam gear, a centrifugal member, and a cover member comprising an integrally formed biasing means for biasing and retaining the centrifugal member in the cam gear. The biasing means urges the centrifugal member into a decompression position when the cam gear is rotating at a lower speed, wherein a projecting portion of the centrifugal member actuates the valve mechanism to reduce the starting force required to start the engine. During normal engine operation, the centrifugal member pivots into a non-decompression position wherein the projecting portion of the centrifugal member recedes below the cam profile surface so as to prevent the projecting portion from actuating the valve mechanism.

Abstract: An automatic decompression mechanism for selectively actuating a cylinder valve of an engine so as to reduce the starting force required to start the engine. The mechanism includes a cam gear, a centrifugal member, and a cover member comprising an integrally formed biasing means for biasing and retaining the centrifugal member in the cam gear. The biasing means urges the centrifugal member into a decompression position when the cam gear is rotating at a lower speed, wherein a projecting portion of the centrifugal member actuates the valve mechanism to reduce the starting force required to start the engine. During normal engine operation, the centrifugal member pivots into a non-decompression position wherein the projecting portion of the centrifugal member recedes below the cam profile surface so as to prevent the projecting portion from actuating the valve mechanism.