A master bicycle electric component includes a bicycle mounting part and a master two-way wireless communication unit. The bicycle mounting part is configured to mount the master bicycle electric component to a bicycle. The master two-way wireless communication unit is configured to wirelessly receive update information from an external terminal device that is not mounted to the bicycle. The external terminal device is separate and remote from the master bicycle electric component. In a case where the update information includes information for updating at least one of software and firmware of at least one slave bicycle electric component, the master bicycle electric component is configured to wirelessly transmit the update information to the at least one slave bicycle electric component directly.