Patent ID: 7078891

Claim:
A speedometer gear output structure comprising: a gearbox fastened to the front fork of a motorcycle, said gearbox comprising a driven gear rotatable with the wheels of the motorcycle, an output gear meshed with said driven gear, and a receiving chamber corresponding to said output gear, said output gear having a gear shaft, said receiving chamber having an extended circuit board recess portion extending therefrom; an annular magnetic device mounted on the gear shaft of said output gear for synchronous rotation, said annular magnetic device having at least one magnetic zone; and a circuit board mounted in the recess portion of said receiving chamber of said gearbox in adjacent relation to said annular magnetic device for directly magnetically coupling said annular magnetic device to said circuit board, said circuit board comprising a sensor facing said annular magnetic device and adapted to output an output signal indicative of speed of rotation of said annular magnetic device and said output gear upon running of the motorcycle, and a signal line extended from said sensor and connected to an electronic speedometer at the motorcycle in which said gearbox is installed for transmitting the output signal of said sensor to the electronic speedometer.