A bicycle control system is basically provided with a power supply, a first bicycle electric component and a controller. The first bicycle electric component is electrically connected to the power supply to receive electrical power from the power supply. The controller is programmed to monitor an electrical communication of the first bicycle electric component. The controller is further programmed to stop electrical power from the power supply to the first bicycle electric component upon determining no electrical communication to or from the first bicycle electric component for a first predetermined inactivity period.