Abstract: The invention is a gear shift device for bicycles, comprising: gear shift control components (A1) suited to transmit codified and/or non-codified signals; actuator components (A3.1, A3.2) suited to be applied to the derailleurs (B4.1, B4.2) and suited to receive said signals and at least one management control unit (A2) of said signals. The device comprises a piece of equipment suited to generate electric energy for powering one or more of said control components (A1) and/or said unit (A2) and/or said actuators (A3.1, A3.2) and/or for charging/recharging one or more possible batteries.