Valve driving device for an engine

摘要

A valve driving device including a tappet assembly adapted to slide in a tappet guide hole to drive a valve and including a high-speed center tappet and low-speed side tappet; and a high-speed center cam and a low-speed side cam provided corresponding to the center tappet and the side tappet. A depression is formed which is depressed from a base circle to roughly the same profile as a shaft section of the camshaft so that the cam portion over a predetermined angle range where a cam nose section is not formed in the centrally located center cam is smaller than the base circles of the outside located side cams in profile.