Abstract: In an exhaust system for a motorcycle in which an engine main body of a multi-cylinder engine has an oil pan on a lower portion thereof, and is mounted on a vehicle body with a plurality of expansion chambers being connected to a downstream side of an assembled portion of a plurality of exhaust pipes that extend out of the respective cylinders of the engine main body, respectively. The muffler includes a first expansion chamber that is connected to the assembled portion and the other expansion chambers that are the assembled portion are disposed on one side of the oil pan. The first continuous to the first expansion chamber. The respective exhaust pipes and expansion chamber is disposed on the other side of the oil pan with the other expansion chambers being disposed to the rear of the engine main body.

Abstract: In an exhaust system for a motorcycle in which an engine main body of a multi-cylinder engine has an oil pan on a lower portion thereof, and is mounted on a vehicle body with a plurality of expansion chambers being connected to a downstream side of an assembled portion of a plurality of exhaust pipes that extend out of the respective cylinders of the engine main body, respectively. The muffler includes a first expansion chamber that is connected to the assembled portion and the other expansion chambers that are continuous to the first expansion chamber. The respective exhaust pipes and the assembled portion are disposed on one side of the oil pan. The first expansion chamber is disposed on the other side of the oil pan with the other expansion chambers being disposed to the rear of the engine main body.

Abstract: The invention is directed at a device that reduces the size of an engine in the direction along the axis of a crankshaft. More specifically, it relates to an engine starting system in which a part of a starting power transmission gear train is provided between one end portion of a crankshaft rotatably borne on a crankcase and a starter motor mounted to the crankcase is covered from the outside by an accessory coupled to and operated in conjunction with the crankshaft.

Abstract: A lubricating structure for an engine includes a crankcase for supporting a crankshaft formed from a pair of case halves coupled to each other along a mating plane extending along a plane perpendicular to an axial line of the crankshaft. An oil reservoir in a lower portion of the crankcase extends across the mating plane. A pump chamber of an oil pump is formed between the two case halves across the mating plane. Lubricant is drawn from the oil reservoir into the oil pump using a structure which can achieve reduction of the number of parts and improve the ease of assembly. The structure includes a path groove, which forms an oil suction path for interconnecting the oil pump and the oil reservoir, formed in at least one of the two case halves.

Abstract: In an engine starting unit, a gear switching clutch is fitted on one end of a main shaft, a power transmission gear train including a clutch gear rotating together with an input member of the gear switching clutch is provided between one end of a crankshaft and the input member, a kick start gear train is arranged between a drive gear group and the clutch gear, and a one-way starter clutch is arranged on the crankshaft between the drive gear group and the clutch gear.

Abstract: A cylinder block, a cylinder head and a cylinder head cover are stacked in order to form a four-cycle engine. A valve train of a single overhead camshaft (SOHC) type provided with an intake valve and an exhaust valve is provided in the cylinder head. A line extending parallel with a joint between the cylinder head and the cylinder head cover is inclined forward and downward toward a line parallel with a joint between the cylinder block and the cylinder head. An axis of an exhaust valve and/or an axis of a plug tube is/are perpendicular to the line extending parallel with the joint between the cylinder head and the cylinder head cover. A cylinder head hanger is integrally formed at an uppermost end of a rear portion of the cylinder head over an intake port.

Abstract: A decompression device is provided for an internal combustion engine having a cylinder head provided with a pair of left and right camshaft bearings sandwiching intake valves and exhaust valves with a structure that is both simple and small. A camshaft is provided having cam projections for at least a pair of intake cams between camshaft side bearings corresponding to the pair of left and right bearings, and a decompression member with a decompression cam with a centrifugal weight arranged at a camshaft end passing through the bearing close to the camshaft end so that a tip thereof is arranged in the vicinity of the cam projections, with the decompression member comprising the centrifugal weight, the decompression cam, and a rotatable shaft coupling the centrifugal weight and the decompression cam in an integral manner.

Abstract: A lubricating structure for an engine includes a crankcase for supporting a crankshaft formed from a pair of case halves coupled to each other along a mating plane extending along a plane perpendicular to an axial line of the crankshaft. An oil reservoir in a lower portion of the crankcase extends across the mating plane. A pump chamber of an oil pump is formed between the two case halves across the mating plane. Lubricant is drawn from the oil reservoir into the oil pump using a structure which can achieve reduction of the number of parts and improve the ease of assembly. The structure includes a path groove, which forms an oil suction path for interconnecting the oil pump and the oil reservoir, formed in at least one of the two case halves.

Abstract: The invention is directed at a device that reduces the size of an engine in the direction along the axis of a crankshaft. More specifically, it relates to an engine starting system in which a part of a starting power transmission gear train is provided between one end portion of a crankshaft rotatably borne on a crankcase and a starter motor mounted to the crankcase is covered from the outside by an accessory coupled to and operated in conjunction with the crankshaft.

Abstract: A decompression device is provided for an internal combustion engine having a cylinder head provided with a pair of left and right camshaft bearings sandwiching intake valves and exhaust valves with a structure that is both simple and small. A camshaft is provided having cam projections for at least a pair of intake cams between camshaft side bearings corresponding to the pair of left and right bearings, and a decompression member with a decompression cam with a centrifugal weight arranged at a camshaft end passing through the bearing close to the camshaft end so that a tip thereof is arranged in the vicinity of the cam projections, with the decompression member comprising the centrifugal weight, the decompression cam, and a rotatable shaft coupling the centrifugal weight and the decompression cam in an integral manner.

Abstract: In an engine starting unit, a gear switching clutch is fitted on one end of a main shaft, a power transmission gear train including a clutch gear rotating together with an input member of the gear switching clutch is provided between one end of a crankshaft and the input member, a kick start gear train is arranged between a drive gear group and the clutch gear, and a one-way starter clutch is arranged on the crankshaft between the drive gear group and the clutch gear.

Abstract: A cylinder block, a cylinder head and a cylinder head cover are stacked in order to form a four-cycle engine. A valve train of a single overhead camshaft (SOHC) type provided with an intake valve and an exhaust valve is provided in the cylinder head. A line extending parallel with a joint between the cylinder head and the cylinder head cover is inclined forward and downward toward a line parallel with a joint between the cylinder block and the cylinder head. An axis of an exhaust valve and/or an axis of a plug tube is/are perpendicular to the line extending parallel with the joint between the cylinder head and the cylinder head cover. A cylinder head hanger is integrally formed at an uppermost end of a rear portion of the cylinder head over an intake port.

Abstract: An electrically powered motor-scooter includes a scooter body having a step floor, a seat, a body cover mounted under the seat, and a storage compartment located below the seat. A battery case is mounted under the step floor which has at least one opening therein which is open to the surrounding air for allowing the flow of air therethrough. A rear compartment extends below and rearwardly of the storage compartment and extends rearwardly of the battery case. The storage compartment forms an upper wall of the rear compartment, and the body cover forms sidewalls of the rear compartment. A portion of the rear compartment is open to the surrounding air. A fan is mounted in a forward portion of the rear compartment for producing a movement of cooling air between the rear compartment and the battery case. The cooling air passes through the rear compartment and the opening in the battery case. A duct is connected between the fan and the battery case which forms a passage for the cooling air to pass therethrough.

Abstract: A battery for an electrically powered vehicle includes a vehicle body having a battery unit operatively connected to the vehicle body for supplying electricity to the electrically powered vehicle. The battery unit is of an elongated shape in outer configuration and is located under the vehicle body with the length direction extending along the longitudinal direction of the vehicle body. A battery unit for an electric motor vehicle includes a battery assembly including a plurality of elongated batteries extending in the longitudinal direction of the motor vehicle and being disposed adjacent to one another with a small gap being provided therebetween. A battery box is provided for accommodating the battery assembly. The battery box includes a front portion, side portions and a rear portion. Ventilation holes are provided in the front portion of the battery box for introducing cool air at positions corresponding to the gap spaces between adjacent individual batteries.

Abstract: A cushioning member is placed in the open slots formed in a core, weirs are disposed at the ends of teeth located on both sides of each of said open slots, a coil composed of a conductor having an insulation film is disposed in said open slots and between said weirs, and said coil is pressed from the opening of said slot toward the bottom thereof in order to deform the cross-sectional shape of the conductor having insulation film from a circular shape into a non-circular shape.