Abstract: A chain change gear for shifting a driving chain to engage a selected one of a set of chain wheels associated with a driven wheel such as the rear wheel of a bicycle includes an articulated lever, a guide piece and first and second joint blocks for transferring movement from the articulated lever to the guide piece. The first joint block is arranged to be fixed to the vehicle frame and the second joint block is arranged to be connected to a chain guiding and tensioning mechanism for moving the mechanism to shift the chain into engagement with the selected one of the chain wheels when the articulated lever is actuated. The guide piece has two first stub axles extending parallel to each other from opposite ends of the guide piece, and the articulated lever has two second stub axles which extend parallel to each other from opposite ends of the articulated lever.