To achieve reduction in manufacturing costs of a one-way clutch device and to improve handleability of a motorcycle. A one-way clutch device includes an inner clutch and an outer clutch with rollers which are provided between the clutches. Weight members include weight main bodies coming into contact with the rollers with arm parts rotatably supported by the inner clutch. If the inner clutch rotates at a rotational speed above a predetermined rotational speed, the weight member moves the roller to a position where the roller allows a connection between the inner clutch and the outer clutch. Moreover, in a motorcycle, the inner clutch of the one-way clutch device is connected to an output side of a power transmission medium, and the outer clutch thereof is connected to a drive wheel.