Patent attributes
An engine valve operating system is provided in which a rocker arm (63) linked and connected to an engine valve (19) and has a cam-abutting portion (65) to abut a valve operating cam (69) is turnably connected, via first and second connecting shafts (64, 66), to one end of a first link arm (61) turnably supported on an engine body (10) and one end of a second link arm (62) turnably supported by a displaceable movable shaft (68a). Also, oil supply means (58) which supply oil to the upper connecting shaft (64) of first and second connecting shafts (64, 66) are fixed to the engine body (10). This makes it possible to implement an engine valve operating system which is compact in size, ensures follow-up ability of the valve opening/closing operation, has a simple lubricating structure with a reduced number of parts, and ensures smooth valve operation while allowing the lift amount of the engine valve to be varied continuously.