A gear reduction apparatus for a bicycle component comprises a gear support, a first gear coupled to the gear support for receiving rotational drive force from a drive component, and a second gear coupled to the gear support for communicating rotational drive force to a driven portion of the bicycle component. The first gear is operatively coupled to the second gear to communicate rotational drive force from the drive component to the driven portion of the bicycle component, and the first gear, the second gear and the gear support are coupled together so that the first gear, the second gear and the gear support may be coupled to and removed from the drive component and the driven portion of the bicycle component as a self-contained unit.