An electric power drive attachment for a wheeled vehicle, as for instance a bicycle, comprising a pair of separate and distinct electric motors mounted adjacent one wheel of the bicycle, the motors being disposed end-to-end and having their shafts in axial alignment. A resilient rubber coupling, having sockets in its ends, receives the shafts and interconnects them for simultaneous turning. The coupling includes a drive roller which engages the bicycle wheel to be driven. A rechargeable battery provides a source of power to drive the motors. The motors preferably have permanent magnet fields and thus can advantageously generate a current when uniquely connected and mechanically driven by the bicycle wheel. Switch means are included to effect connection of the motors in parallel across the battery to drive the bicycle. Provision is also made for connecting the motors in series-aiding relation across the battery to provide efficient charging of the same when the motors are mechanically driven. Alternately, the motors when driven can be connected to a load resistor and thus provide auxiliary electric braking for the bicycle, if necessary. A lever located on the handle bars permits selective engagement and disengagement of the drive roller and the bicycle wheel, to permit the bicycle having the drive attachment to be operated in the conventional manner.
展开▼