Patent ID: 7369929

Claim:
A bicycle gearshift comprising: a rear actuator and a front actuator, each having a respective motor and each actuator displacing a chain through a guide element, the chain being displaced in an axial direction with respect to a respective gearshift group comprising at least two sprockets respectively associated with the hub of the rear wheel and with the axle of the pedal cranks of a bicycle, a signal generator that generates a signal requesting a specified displacement of the chain from a first sprocket to a second sprocket of the respective gearshift group, an electronic control unit connected to the rear actuator and to the front actuator, operating to receive the displacement request signal and to drive the rear or front actuator, respectively, wherein the electronic control unit is suitable for driving the rear or front actuator, respectively, to displace a guide element a predetermined difference in distance between the first sprocket and second sprocket, which in turn moves the chain from the first sprocket to an upwards gear-shifting position for the second sprocket if the first sprocket has a smaller diameter than the second sprocket, to a downwards gear-shifting position for the second sprocket if the first sprocket has a larger diameter than the second sprocket.