Abstract: A protective cover for attachment to an automobile mounted bicycle carrier to preclude exposure of the bicycle to the ambient environment having a back of flexible material with openings therein to permit the cover to be mounted to the carrier, a set of openings in the back to permit a strap to pass therethrough to secure the bicycle to the carrier, a front of flexible material affixed at one edge to the back, a closure having its elements affixed to the free edges of the front and back to permit the cover to be closed to protect the bicycle, the upper portions of the front and back forming a top flap to allow for various seat and handle bar heights, the top flap overlays the front when it is folded down and is cooperatively attachable to the front by means of a Velcro fastener or similar fastening device so that the protective cover is not loose and does not flap in the breeze when the vehicle is in motion.