In printing machines, it is often necessary to move materials at two different speeds, for example, bulk movement from one station to another, and precise movement to effect registration for printing. Disclosed herein is apparatus for transmitting power to a drum from two motors via a single output shaft. The apparatus includes a shaft having a coupling disc at one end which can move axially under the control of an actuator either to engage a flywheel driven by a high speed motor or a drive ring driven by a stepper motor via a gear. The other end of the shaft has a gear which transmits the motor drive to the drum via a gear attached to the drum shaft.