Patent ID: 8276732

Claim:
A clutch device including: a clutch mechanism which is disposed in a power transmission route for transmitting a rotational drive force of an engine to a wheel to connect and disconnect transmission of the rotational drive force; a clutch actuator which operatively engages and disengages the clutch mechanism; a clutch lever which is provided on an operating handlebar and operated by a rider; and an assist pressure generator which generates assist pressure by driving an electric motor in response to the operation of the clutch lever; wherein assist pressure generated by the assist pressure generator is supplied to the clutch actuator and used as an assist force to operatively engage and disengage the clutch mechanism in response to operation of the clutch lever; said clutch mechanism comprising: a lever turning sensor which detects a turning-operation amount of the clutch lever; a gain adjustment device which controllably drives the electric motor on the basis of the operation amount of the clutch lever detected by the lever turning sensor and adjusts a driving force generation gain characteristic of the electric motor; and gain setting means which sets a value for the driving force generation gain characteristic by external operation; wherein gain adjustment device uses the gain characteristic set by the external operation of the gain setting means to controllably drive the electric motor in response to the operation of the clutch lever, wherein the assist pressure generator includes an assist-purpose crankshaft rotatably driven by the electric motor and an assist-purpose cylinder, wherein a rotation driving force of the electric motor is transmitted to the assist-purpose crankshaft via a plurality of idler gears.