Abstract: A fuel tank is provided for a motorcycle having a main body part and a downward swelling part that is opened upward and attached to a bottom part of the fuel tank. The inside of the downward swelling part is connected to the inside of the main body part, thereabove. A fuel pump is provided having a suction part disposed in the downward swelling element and a portion above the suction part installed in the main body part of the fuel tank. A fuel retaining member is also provided in the downward swelling part, whereby fuel retained by the fuel retaining member is sucked by the suction part.

Abstract: A rear wheel suspension for a motorcycle can sufficiently ensure the stroke of a rear cushion and can enhance traveling performance of a vehicle by lowering the gravity center of the vehicle. A swing arm includes an upper arm swingably connecting a body frame with the upper portion of a power transmission portion. A lower arm swingably connects the body frame with the lower portion of the power transmission portion. The axial center of the upper end support portion of a rear cushion is swingably supported by the upper arm at a position forward of the axial center of the support portion. The axial center of the lower support portion of the rear cushion can swingably be supported by the lower arm at a position rearward of the axial center of the support portion swingably supporting the lower arm and the body frame with respect to the vehicle.

Abstract: To realize the reduction of weight of a power transmission device by overcoming a drawback that an excessively large rotational torque is transmitted to a power transmission path and to sufficiently suppress the generation of a change of a rotational speed by overcoming a drawback that phases between one universal joint and another universal joint are displaced from each other. A damper mechanism is provide in the course of a power transmission path from an engine to a final reduction gear. The damper mechanism transmits a torque from the engine until the torque arrives at a predetermined value and prevents the transmission of a torque that exceeds the predetermined value.

Abstract: A rear wheel suspension device of a motorcycle has rear end portions of an upper arm member and a lower arm rotatably joined to a knuckle member, which pivotally supports a rear wheel. The rear wheel suspension device can obtain a progressive cushion property while avoiding an increase in the number of parts. At the same time, the rear wheel suspension device can make the acquisition of extra rigidity of the vehicle body frame unnecessary. One end of a rear cushion unit is joined to one of an upper arm member and a lower arm member. A rear end portion of another of the upper arm member and the lower arm member is rotatably joined to a knuckle member in front of a rear wheel support portion of the knuckle member. Another end of the rear cushion unit is joined to one of another arm member and knuckle member.

Abstract: A fuel tank is provided for a motorcycle having a main body part and a downward swelling part that is opened upward and attached to a bottom part of the fuel tank. The inside of the downward swelling part is connected to the inside of the main body part, thereabove. A fuel pump is provided having a suction part disposed in the downward swelling element and a portion above the suction part installed in the main body part of the fuel tank. A fuel retaining member is also provided in the downward swelling part, whereby fuel retained by the fuel retaining member is sucked by the suction part.