Abstract: The specification discloses apparatus for mounting a loadcarrying apparatus such as a basket (10) to the carrier rack (12) on a conventional bicycle. The clamping assembly (22) includes an upper jaw (26) and a lower jaw (28) dimensioned to engage the horizontal support member (18) of the carrier rack. A bolt extending from lower jaw (28) through the upper jaw (26) is provided for compressing and releasing the clamping assembly. Rotation of a knob (68) threaded through the bolt outside of the upper jaw permits adjustment of the compression exerted by the jaws. A separate releasable locking assembly (24) connected to the loadcarrying structure is provided for receiving and engaging the nonhorizontal support member (20) of the carrier rack. The locking assembly (24) contains a pair of coaxially mounted discs configured to interlock with one another in a variety of rotational positions. A mounting disc (30) is rigidly connected to the loadcarrying structure and interlocks with a locking disc (32).