Abstract: An exhaust pipe connected to an exhaust port of an engine and an expansion chamber is disposed in the vicinity of the engine. A main tube is provided that extends rearwardly from a head pipe disposed at the front side of a main body. An engine having a cylinder extending upwardly from a crankcase is disposed under the main tube with an exhaust port open at the front side of the cylinder. A first exhaust pipe is provided that is connected to the exhaust port. A down tube is disposed on the center line in the left-right direction of the main body. The exhaust port disposed behind the down tube is deviatingly open at one side from the center line. The first exhaust pipe extends forward from one side of the down tube, and to the other side of the down tube, subsequently turns, and extends again to one side.

Abstract: An exhaust pipe connected to an exhaust port of an engine and an expansion chamber is disposed in the vicinity of the engine. A main tube is provided that extends rearwardly from a head pipe disposed at the front side of a main body. An engine having a cylinder extending upwardly from a crankcase is disposed under the main tube with an exhaust port open at the front side of the cylinder. A first exhaust pipe is provided that is connected to the exhaust port. A down tube is disposed on the center line in the left-right direction of the main body. The exhaust port disposed behind the down tube is deviatingly open at one side from the center line. The first exhaust pipe extends forward from one side of the down tube, and to the other side of the down tube, subsequently turns, and extends again to one side.

Abstract: A concave portion and a convex portion are provided to the end face of a lever cover and a face opposite to the end face on the side of a dial member, a hexagonal head of an adjusting bolt is fitted into a hexagonal hole of the dial member, and a flange of the lever cover is covered with the dial member so that the concave portion and the convex portion are fitted and the flange of the lever cover is fitted into an annular groove. The adjustment of the quantity in which clutch wire is pulled can be easily determined and the fine adjustment of the quantity can be precisely made as desired.

Abstract: A concave portion and a convex portion are provided to the end face of a lever cover and a face opposite to the end face on the side of a dial member, a hexagonal head of an adjusting bolt is fitted into a hexagonal hole of the dial member, and a flange of the lever cover is covered with the dial member so that the concave portion and the convex portion are fitted and the flange of the lever cover is fitted into an annular groove. The adjustment of the quantity in which clutch wire is pulled can be easily determined and the fine adjustment of the quantity can be precisely made as desired.

Abstract: By providing a main flame extending from a head pipe and a radiator below a front part of the main frame in a motorcycle having the radiators arranged to the side of the vehicle, it becomes possible to arrange the radiator close to the main frame by providing an upper indentation in an upper corner of an upper tank towards the center of the vehicle. It also becomes possible to arrange the radiator close to an exhaust pipe by providing a lower indentation in a lower outer corner of the lower tank. An upper tank and a lower tank are the same molded part and can therefore be made with a single mold. Since the upper indented sections are provided, there is no interference between the main frame and the radiator. Since the lower indented sections are provided, there is no interference between the mainframe and an exhaust pipe. Furthermore, it is possible to increase the core surface area (heat radiation characteristics) of the middle of the radiator.

Abstract: A motorcycle air cleaner system arranged behind a rear suspension damper. A connecting tube extends from an outlet in an air cleaner so that air for combustion flows sequentially through the air cleaner and the connecting tube. A front surface of the air cleaner is brought close to the rear suspension damper by providing a recessed section for providing clearance for the rear suspension damper. An expanded portion of the connecting tube adjacent the recessed section increases the capacity of the air cleaner.

Abstract: A part attachment hole for attaching an accessory part, such an ignition plug, is formed in a substantially central part of a cylinder head of a water-cooled engine. A plurality of cylinder block attachment bolt holes are formed around the part attachment hole at a substantially equal pitch. A plurality of hose connection openings are formed between the plurality of cylinder block attachment bolt holes. Furthermore, a single radiator is connected via a radiator hose to the plurality of hose connection openings of the cylinder head having the above structure.

Abstract: In a motorcycle with a pair of left and right steps mounted in a projecting manner on a lower portion of a vehicle body, a pair of left and right brake pedals capable of independently operating the rear wheel brake are pivoted on the vehicle body in close vicinity to the left and right steps, respectively. When a driver turns the motorcycle in either left or right direction with his one foot being placed on the ground, the driver can operate the rear wheel brake using the opposite foot.