Valve operating apparatus is disclosed in which the valves are operated by transmitting members in the form of rocker arms or bucket lifters driven by cams having different cam profiles and coupling devices for selectively connecting or disconnecting adjacent transmitting members to vary the operation of the valves under different engine operating conditions. The transmitting member that is not directly associated with a valve and that idles when not coupled to an adjacent transmitting member is spring biased toward the operating cam by an abutment member and means are provided to limit the stroke of the abutment member.