Abstract: A mechanism for varying the lift, timing and duration of a valve member associated with an internal combustion engine comprising an elongated rocker arm having a first pivot end and a second end forming a valve member actuating free end, a pair of eccentric members forming a first eccentric member and a second eccentric member collectively defining a pivot axis within a circular opening for the rocker arm, the first eccentric member comprising a shaft having cylindrical end portions journaled for rotation about a shaft axis and an eccentric cylindrical portion located within the opening of the rocker arm, and the second eccentric member comprising a tubular sleeve rotatably supported on the surface of the shaft and concentric with a second eccentric axis spaced from the shaft axis, the second eccentric member rotating relative to the first eccentric member to provide a pivot axis for the rocker arm which is formed by the collective angular position of the first and second eccentric members.