Abstract: A power transmission for a two-wheeled vehicle includes a variable-diameter drive pulley mechanism (2) mounted on a drive shaft (1) connected to an engine (E), a variable-diameter driven pulley mechanism (22) mounted on a driven shaft (18) operatively coupled with a driven wheel (W), and a clutch (36) mounted coaxially on the driven shaft (18) and operatively connected to the driven pulley mechanism (22). The drive and driven pulley mechanisms (2,22) are interconnected by a V-belt (7). The drive and driven pulley mechanisms (2,22) have axially movable members (5,24) located on opposite sides of the V-belt (7) adjacent to the engine (E) and the clutch (36) to allow parallel displacement of the V-belt (7) during the changing of the diameters of the pulley mechanisms (2,22), to prevent belt twisting or distortion and to prevent the belt (7) and pulley mechanisms (2,22) from being loaded while the vehicle is moved around with the engine (E) turned off.

Abstract: A power transmission casing apparatus in a motorized two-wheeled vehicle which comprises a case main body extending from one lateral side of an internal combustion engine to one lateral side of a rear wheel in rear thereof and supporting rotatably a wheel axle of the rear wheel. The case main body is applied with a cover member for containing therein liquid-tightly a reduction gear means, and is applied with another cover member for containing therein a V-belt means.

Abstract: A method for pressure bonding metal members by utilizing eutectic reaction comprising the steps of bringing two metal members of dissimilar metals to be bonded into contact with each other under a predetermined contacting pressure P.sub.1 lower than the plastic deformation pressures of the metals of the two members and heating the contacting surfaces of the two members to a temperature lower than melting point temperatures of the metals and not lower than the eutectic temperature thereof to produce a liquid of eutectic composition by eutectic reaction between the surfaces of the two members to be bonded, applying an upset pressure P.sub.2 higher than the contacting pressure P.sub.1 to the surfaces to be bonded to squeeze out the liquid from the contacting surfaces of the two members to outside, and cooling the bonded surfaces of the two members.

Abstract: A power transmission apparatus in which a crank shaft of an internal combustion engine, an input shaft of a speed-change mechanism and an output shaft of the speed-change mechanism are arranged in three parallel rows, the input shaft being provided at an end portion with a torque convertor drivingly coupled to the crank shaft. At least two gears are provided on the input shaft and are in mesh with respective gears rotatably mounted on the output shaft. The output shaft is provided at an intermediate portion between the two gears thereon with a shift member which is connected for common rotation with the output shaft but is slidable thereon in axial direction. Between each end surface of the shift member and a facing surface of the gear on the output shaft there is interposed a dog clutch comprising pins on one surface and pin openings in the other surface.