Abstract: For use with a quick release mechanism of the quick release lever type for selectively securing and releasing the front wheel of a bicycle relative to the front fork thereof, or the seat post relative to the seat post socket, or the front fork to a vehicle bicycle rack, a lock device including a pivoted blade and controlled by lock engaging means, such as a key, enables or disables the operation of the lever and thus the quick release mechanism by moving the blade between a first position in non-interfering relation with the movement of the quick release lever and a second position in interfering relation therewith.