Abstract: A vehicle includes a front wheel, a rear wheel, and a power unit. The power unit is disposed between the front wheel and the rear wheel in a front-rear direction of the vehicle. An internal combustion engine and a compressor are modularized. The compressor is configured to operate on rotational power generated in the internal combustion engine. The internal combustion engine includes a crankshaft and an output shaft. Rotation axes of the crankshaft and the output shaft are parallel to each other and extend in the front-rear direction of the vehicle. The compressor is disposed on one side of the crankshaft in a left-right direction. The output shaft is disposed on the other side of the crankshaft in the left-right direction.

Abstract: A power unit structure includes a driving shaft of a driving source, and a driven shaft interlocked with the driving shaft, the structure of a power unit further includes an auxiliary machinery driven by receiving a rotational motion of an output shaft which is one of the driving shaft and the driven shaft, an auxiliary machinery input shaft disposed coaxially with the output shaft is connected to the auxiliary machinery, and a connecting portion configured to integrally rotatably connect the auxiliary machinery input shaft is formed integrally with the output shaft.

Abstract: A power unit has an internal combustion engine and a first auxiliary machine. The internal combustion engine includes a crankshaft and a balancer shaft. The first auxiliary machine operates on rotational power generated in the internal combustion engine. The first auxiliary machine is driven by rotational power of the balancer shaft.

Abstract: A vehicle includes a front wheel, a rear wheel, a power unit in which an internal combustion engine and a compressor are modularized, and a seat. The compressor is configured to operate on rotational power generated in the internal combustion engine. The power unit is disposed between the front wheel and the rear wheel in a front-rear direction of the vehicle, and is disposed to place the compressor below the seat.

Abstract: An oil passageway structure for IC engines includes a generator provided on one end side of a crankshaft, a generator cover that covers the generator and is fixed to an engine crankcase, a protective cover provided outside the generator cover and a water pump attached to an outer surface of the protective cover and having a drive shaft coaxially connected to one end of the crankshaft. The generator cover includes oil passageways that supply engine oil from the crankcase to the generator, and a generator cover-side guide portion that flows out engine oil collected from a generator housing space housing the generator toward the protective cover, and the protective cover includes a protective cover-side guide portion that guides and supplies the engine oil flowing out from the generator cover-side guide portion to the drive shaft of the water pump.

Abstract: A vehicle includes a front wheel, a rear wheel, and a power unit. The power unit is disposed between the front wheel and the rear wheel in a front-rear direction of the vehicle. An internal combustion engine and a compressor are modularized. The compressor is configured to operate on rotational power generated in the internal combustion engine. The internal combustion engine includes a crankshaft and an output shaft. Rotation axes of the crankshaft and the output shaft are parallel to each other and extend in the front-rear direction of the vehicle. The compressor is disposed on one side of the crankshaft in a left-right direction. The output shaft is disposed on the other side of the crankshaft in the left-right direction.

Abstract: An oil passageway structure for IC engines includes a generator provided on one end side of a crankshaft, a generator cover that covers the generator and is fixed to an engine crankcase, a protective cover provided outside the generator cover and a water pump attached to an outer surface of the protective cover and having a drive shaft coaxially connected to one end of the crankshaft. The generator cover includes oil passageways that supply engine oil from the crankcase to the generator, and a generator cover-side guide portion that flows out engine oil collected from a generator housing space housing the generator toward the protective cover, and the protective cover includes a protective cover-side guide portion that guides and supplies the engine oil flowing out from the generator cover-side guide portion to the drive shaft of the water pump.

Abstract: A power unit includes: a crankcase which accommodates a crankshaft and a main shaft arranged in parallel to each other; a crank side cover which covers one end portion of the crankshaft from the outside in an axial direction of the crankshaft; a primary driven gear which is provided in the main shaft and meshes with a primary drive gear of the crankshaft; a clutch provided at one end portion of the main shaft; and a clutch cover which covers the clutch from the outside in an axial direction of the main shaft and is fastened and fixed to a packing surface provided on the crankcase to surround the clutch, wherein the primary driven gear and the packing surface overlap in a virtual straight line when viewed from the axial direction of the main shaft.

Abstract: An internal combustion engine includes a reduction gear including: at one end thereof, a small-diameter gear in mesh with a one-way clutch gear; and at an opposite end thereof, a large-diameter gear in mesh with a drive gear of a starter motor. The starter motor has a driveshaft disposed below a rotation axis of the reduction gear and within a width of the large-diameter gear as viewed in an axial direction. Accordingly, in the internal combustion engine, it is possible to efficiently dispose components in a reentrant space formed between a crankcase and a cylinder block.

Abstract: An engine includes: a crankcase; a cover that is connected to the crankcase at a mating surface of the cover inclined toward an inner side in a vehicle width direction in going downward when the engine is mounted to a vehicle body, the cover covering a protruding end of a rotary shaft; and attachment bosses that are formed to be integral with the cover, have a predetermined height from the mating surface, and accept fastening members for fastening the cover to the crankcase. Accordingly, when mounted on a two-wheeled motor vehicle, the engine can restrain protrusion in the vehicle width direction and can be disposed at a position as low as possible with reference to the vehicle.

Abstract: As viewed from a side, an output shaft is disposed rearward of a crankshaft, and an odd-numbered stage shaft and an even-numbered stage shaft are disposed rearward of the crankshaft. Moreover, the odd-numbered stage shaft is provided on a side opposite to the even-numbered stage shaft relative to a line connecting the crankshaft and the output shaft, and a shift drum is disposed on a side opposite to the output shaft relative to a line connecting the odd-numbered stage shaft and the even-numbered stage shaft. This structure reduces dimensions of the power unit for the saddled vehicle.

Abstract: In an engine, a cylinder block and a cylinder head are connected with a crankcase in a forwardly inclined posture. A dual clutch connects or disconnects a transmission path of power of the engine to a transmission. An actuator chamber houses an actuator that controls a hydraulic pressure of the dual clutch. The actuator chamber is disposed on an upper surface of the cylinder block at a position posterior to the cylinder head and anterior to the crankcase in a vehicle longitudinal direction.

Abstract: An internal combustion engine includes: an oil filter that is mounted to a mounting surface formed on a crankcase and clarifies an oil flowing in; an oil cooler that is disposed on a front side of the crankcase, cools the oil flowing in from the oil filter and returns the oil into a flow path in the crankcase; and a bracket formed on a front wall of the crankcase and having the mounting surface. An outflow port through which the oil flows out toward the oil cooler and an inflow port through which the oil flows in from the oil cooler are disposed in the bracket. Accordingly, in the internal combustion engine, routes of oil passages can be simplified as much as possible.

Abstract: In an engine, a cylinder block and a cylinder head are connected with a crankcase in a forwardly inclined posture. A dual clutch connects or disconnects a transmission path of power of the engine to a transmission. An actuator chamber houses an actuator that controls a hydraulic pressure of the dual clutch. The actuator chamber is disposed on an upper surface of the cylinder block at a position posterior to the cylinder head and anterior to the crankcase in a vehicle longitudinal direction.

Abstract: A power unit includes: a crankcase which accommodates a crankshaft and a main shaft arranged in parallel to each other; a crank side cover which covers one end portion of the crankshaft from the outside in an axial direction of the crankshaft; a primary driven gear which is provided in the main shaft and meshes with a primary drive gear of the crankshaft; a clutch provided at one end portion of the main shaft; and a clutch cover which covers the clutch from the outside in an axial direction of the main shaft and is fastened and fixed to a packing surface provided on the crankcase to surround the clutch, wherein the primary driven gear and the packing surface overlap in a virtual straight line when viewed from the axial direction of the main shaft.

Abstract: An internal combustion engine includes: an oil filter that is mounted to a mounting surface formed on a crankcase and clarifies an oil flowing in; an oil cooler that is disposed on a front side of the crankcase, cools the oil flowing in from the oil filter and returns the oil into a flow path in the crankcase; and a bracket formed on a front wall of the crankcase and having the mounting surface. An outflow port through which the oil flows out toward the oil cooler and an inflow port through which the oil flows in from the oil cooler are disposed in the bracket. Accordingly, in the internal combustion engine, routes of oil passages can be simplified as much as possible.

Abstract: An internal combustion engine includes a reduction gear including: at one end thereof, a small-diameter gear in mesh with a one-way clutch gear; and at an opposite end thereof, a large-diameter gear in mesh with a drive gear of a starter motor. The starter motor has a driveshaft disposed below a rotation axis of the reduction gear and within a width of the large-diameter gear as viewed in an axial direction. Accordingly, in the internal combustion engine, it is possible to efficiently dispose components in a reentrant space formed between a crankcase and a cylinder block.

Abstract: An engine includes: a crankcase; a cover that is connected to the crankcase at a mating surface of the cover inclined toward an inner side in a vehicle width direction in going downward when the engine is mounted to a vehicle body, the cover covering a protruding end of a rotary shaft; and attachment bosses that are formed to be integral with the cover, have a predetermined height from the mating surface, and accept fastening members for fastening the cover to the crankcase. Accordingly, when mounted on a two-wheeled motor vehicle, the engine can restrain protrusion in the vehicle width direction and can be disposed at a position as low as possible with reference to the vehicle.

Abstract: As viewed from a side, an output shaft is disposed rearward of a crankshaft, and an odd-numbered stage shaft and an even-numbered stage shaft are disposed rearward of the crankshaft. Moreover, the odd-numbered stage shaft is provided on a side opposite to the even-numbered stage shaft relative to a line connecting the crankshaft and the output shaft, and a shift drum is disposed on a side opposite to the output shaft relative to a line connecting the odd-numbered stage shaft and the even-numbered stage shaft. This structure reduces dimensions of the power unit for the saddled vehicle.

Abstract: A hybrid power unit is mounted on a vehicle body frame of a saddle-type vehicle and is composed of an engine, a transmission, a clutch system, that enables switching between connection and disconnection of power transmission between a crankshaft and the transmission, and an electric motor capable of transmitting rotational power to the transmission. An operation of the electric motor alone is enabled with alleviation of the load. Thus, an increase in the size in the direction along the axis line of the crankshaft is avoided. The electric motor, rendered incapable of direct power transmission from and to a crankshaft, is housed in a transmission chamber so as to be allowed to transmit rotational power from a rotor of the electric motor to a transmission shaft. The rotor is disposed on an upper side relative to the highest oil level of lubricating oil in the transmission chamber.