Abstract: The jockey wheel, intended to be incorporated in the derailleur of a bicycle, permits limited lateral sliding movement of its outer ring gear relative to a central bushing, but requires a rolling bearing between the outer ring gear and the central bushing to rotate by fixing the ring gear to the outer race of the rolling bearing and the bushing to the inner race of the rolling bearing. In one construction, bushings between the inner race and shaft carrying the jockey wheel are keyed to one another to permit only lateral sliding movement. In another construction, the inner race of the rolling bearing is eccentrically shaped to interfit with the bushing, thereby permitting only lateral sliding movement between the eccentrically shaped inner race and bearing but requiring the inner race to rotate with the bushing.