Patent ID: 7740263

Claim:
A front wheel supporting structure for a motorcycle, comprising a pair of front forks provided on the right and left sides of a front wheel of the motorcycle for supporting the front wheel to a frame of the motorcycle, wherein the pair of the front forks comprises: a first front fork which generates a damping force for damping a vibration of the front wheel depending on an amplitude of the vibration; and a second front fork which generates a damping force for damping a vibration of the front wheel not depending on the amplitude of the vibration, wherein an end of the first front fork is connected to the frame, and the other end of the first front fork is connected to a shaft of the front wheel, such that the first front fork elongates and contracts according to the vibration of the front wheel; and the first front fork includes a damping force generating mechanism which generates a damping force when the first front fork contracts, the damping force generating mechanism including: a cylinder, a piston which separates an interior of the cylinder into a rod side oil chamber and a piston side oil chamber, and is slidable in the cylinder in a direction for reducing the piston side oil chamber formed in the cylinder as the first front fork contracts, a plurality of through-holes formed through a wall of the cylinder for allowing working oil with which the piston side oil chamber is filled to flow out from the piston side oil chamber, the through-holes being disposed along a sliding direction of the piston such that a number of the through-holes on the piston side oil chamber decreases as the piston reduces the piston side oil chamber; and a check valve which prevents the working oil from flowing into the rod side oil chamber from the piston side oil chamber, and allows the working oil to flow into the piston side oil chamber from the rod side oil chamber, such that only a small damping force is generated in an elongation stroke.