US Patent 7565944 Power steering system for all-terrain vehicle

To provide a power steering system for an all-terrain vehicle in which a control unit can be favorably protected from water, mud or the like coming from the ground surface at the time of operating of the vehicle on rough terrain or the like. In a power steering system for a saddle ride type four-wheel vehicle in which a rotary shaft of a power assist motor is disposed at right angles to a steering shaft and is inclined so that its upper portion is located on the rear side, a control unit for controlling the power assist motor is disposed on the upper side relative to a meshed portion between the power assist motor and the steering shaft.