Abstract: An electric auxiliary drive for a pedal-driven road vehicle is provided. The drive comprises an electric motor, a rechargeable multicell battery to power the motor and switch means to control the motor. The motor is adapted to operate in a first mode in which it functions as a mover, drawing energy from the battery and imparting it to the vehicle, and in a second mode in which it functions as a generator, drawing energy from the vehicle and imparting it to said battery. There is further provided a first transmission means to provide a permanent kinematic connection between the motor and the pedal axle of the vehicle for the moving thereof when operating in the first mode and a second transmission means to selectively provide a kinematic connection between one wheel of the vehicle and the motor, to enable the motor to operate in the second mode.