An apparatus includes a bicycle frame defining a bore, and a bicycle seat assembly including a post received in the bore. An indicating unit is configured to indicate a first position of the post along the bore for a first user and a second position of the post along the bore for a second user. An identification unit is configured to identify the first user and the second user. A computing device includes a processor and a memory, the memory storing instruction such that the processor is programmed to instruct the indicating unit to indicate the first position when the identification unit identifies the first user and to instruct the indicating unit to indicate the second position when the identification unit identifies the second user.