A brake system includes a driving part driven by electric power to brake a rotary body of a human-powered vehicle and an electronic controller configured to control the driving part. The electronic controller has a plurality of control modes including a first mode that drives the driving part in accordance with a user operation and a second mode that does not drive the driving part regardless of the user operation. The electronic controller is configured to switch the plurality of control modes based on setting information related to an input to the human-powered vehicle.