Abstract: An engine for a motorcycle includes an engine case split in an upper case section and a lower case section. A mating surface between the upper case section and the lower case section extends linearly and inclines forward downward in a side view of the motorcycle. A crankshaft, a transmission input shaft, and a balancer shaft extending in the width direction of the motorcycle are rotatably supported at the mating surface, and a transmission output shaft rotated by the transmission input shaft is supported in the lower case section. The balancer shaft, the crankshaft, and the transmission input shaft are arranged in that order from the front side in the running direction of the motorcycle. The transmission output shaft is disposed below the transmission input shaft.

Abstract: An engine includes an engine case split into an upper case and a lower case. A crankshaft and a transmission input shaft are rotatably supported at a mating surface between the upper and lower cases, and a transmission output shaft rotated by the transmission input shaft is supported in the lower case. One side face of the lower case has a circular opening through which the transmission output shaft can be inserted from the outside. An eccentric bearing holder holding a bearing that rotatably supports one end of the transmission output shaft is mounted in the opening in a detachable manner from the outside. The axis of the transmission output shaft deviates from the center of the eccentric bearing holder toward the transmission input shaft. The inner diameter of the opening is larger than the outer diameter of the largest one of transmission driving gears of the transmission input shaft.

Abstract: An engine for a motorcycle includes an engine case, a crankshaft rotatably supported within the engine case and extending laterally, an intermediate shaft being substantially parallel to the crankshaft and being rotated by the crankshaft at the same speed via a primary drive gear and a primary driven gear, a transmission input shaft being substantially parallel to the intermediate shaft and being rotated by the intermediate shaft at reduced speed via a secondary drive gear and a secondary driven gear, a transmission output shaft being substantially parallel to the transmission input shaft and being rotated by the transmission input shaft at changed speed via any combination of a plurality of transmission drive gears and transmission driven gears, and a clutch unit disposed on the intermediate shaft and capable of transmitting and interrupting rotation of the intermediate shaft to the transmission input shaft.

Abstract: A motorcycle includes an exhaust device connected to an engine unit, and the exhaust device includes: a plurality of first exhaust pipes forwardly extending from an exhaust port which opens in the front of the engine unit; a joint portion for joining the first exhaust pipes; a second exhaust pipe connected to a downstream side of the joint portion and passing below an oil pan disposed in a lower portion of the engine unit; and an exhaust expansion chamber connected to a downstream portion of the second exhaust pipe. A cowling of such a motorcycle includes: a front cowling covering the engine unit and the exhaust device from lower and side portions thereof; and a rear cowling partially covering a rider's seat. The front cowling is formed with an air-exhaust opening at a bottom surface of a rear end thereof positioned to a front lower surface of the exhaust expansion chamber.

Abstract: An engine unit for an motorcycle is disclosed in which an accessory drive gear is disposed downstream of primary dampers in the engine power transmission path, and simultaneously upstream of a clutch mechanism in the engine power transmission path. In this engine unit, an accessory, for example, generator, is connected to an intermediate shaft that is parallel to a crank shaft and a counter shaft so as to rotate integrally with the intermediate shaft. An accessory driven gear is meshed with the accessory drive gear, and an accessory damper is disposed between the intermediate shaft and the accessory for absorbing rotational shocks. Furthermore, a starter motor is gear-engaged with the intermediate shaft via a one-way clutch, and the position of this gear engagement is provided between the accessory damper and the accessory driven gear.

Abstract: In a snowmobile, an upper front half of a vehicle body of the snowmobile is covered to be openable by an engine hood in which an engine room is defined, an engine is disposed in the engine room, and a turbo-charger is mounted on the engine. In an engine structure of such snowmobile, a headlight is disposed above a rear portion of the engine hood, and the engine is arranged in a state inclined rearward downward so that a cylinder head of the engine is disposed below the headlight in a side view and the turbo-charger is arranged below the cylinder head.

Abstract: An exhaust system for a motorcycle having an engine mounted on a front half of a body frame of the motorcycle includes a plurality of first exhaust pipes extending from exhaust ports of the engine, a collecting section at which the first exhaust pipes are collected, a second exhaust pipe including a substantially straight portion connected to a downstream side of the collecting section and disposed under a crankcase of the engine, an expansion chamber connected to a downstream side of the second exhaust pipe and located under a rear wheel suspension arranged behind the engine, an exhaust outlet disposed on a most downstream portion of the expansion chamber, and an exhaust throttle valve and an exhaust gas sensor disposed on the straight portion of the second exhaust pipe.

Abstract: An outboard motor comprises an engine disposed inside an outer cover, an intake unit provided for the engine and including a throttle body disposed in a vicinity of a crankcase of the engine and an intake manifold disposed on a side of the engine so as to extend from the throttle body, the intake manifold having a plurality of intake pipes extending towards intake ports formed in a cylinder head of the engine, and a fuel injectors disposed in substantially intermediate portions of the respective intake pipes.

Abstract: An outboard motor includes an upright engine in which a plurality of cylinders are arranged vertically, an engine cover covering the engine, and an intake system for the engine. The intake system includes an intake manifold disposed on a side of the engine and provided with a surge tank and an intake pipe, in which the surge tank is arranged on the side of the engine inside the engine cover, the intake pipe is arranged on the inner surface side of the engine cover therein in a manner that the surge tank and the intake pipe are arranged parallel to each other.

Abstract: An outboard motor is provided with a four-stroke-cycle engine and an oil pan disposed below the engine. In the arrangement of the oil pan, a lubricating oil reservoir is arranged on a front side of the oil pan, and an exhaust gas passage and a cooling water passage are arranged on the rear side of the lubricating oil reservoir.

Abstract: An intake device of a V-type engine provided with two cylinders inclining in a longitudinal direction of a motorcycle includes a center air cleaner arranged above a V-bank space formed between the two cylinders, a pair of right and left side air cleaners arranged on both sides of the V-bank space, and an air/fuel mixture supply device disposed between the center air cleaner and the V-bank space. An internal space of the center air cleaner is communicated with an intake port of each of the cylinders through the air/fuel mixture supply device. The internal space of the side air cleaner is divided into a dirty side and a clean side with an air filter being interposed therebetween, in which the clean side is connected to the center air cleaner and the dirty side is provided with an intake port communicating with an outside. The intake port is opened so as to face the V-bank space side.

Abstract: A conveyor for guiding and conveying a plurality of sheet-shaped thin plates in rows arranged side by side to a welding position at which ends of the adjacent thin plates are butted and welded to each other, includes a plurality of conveying paths, which are adjacent to each other, having different conveying surfaces which are placed on a same horizontal plane, and a guide unit disposed between the adjacent two conveying paths for guiding the thin plates on one of the conveying paths with respect to another one thereof toward the welding position. Each of the conveying paths is composed of a plurality conveying rollers, and the guide unit includes guide rollers each having a guide surface for guiding the thin plate on the one of the conveying paths in a state that the thin plate on the one conveying path is partially depressed with respect to the another one of the conveying path.

Abstract: An outboard motor has a V-type engine in which in which a plurality of cylinders are arranged in a V-shape, a crankshaft is arranged substantially vertically, and an overhead valve (OHV)-type valve train is mounted. This outboard motor also includes an air intake system in which a carburetor is arranged above the engine and in a space of a V bank between the cylinders.

Abstract: A four-stroke-cycle engine of a vehicle such as snowmobile comprises a crank case, which is dividable into a plurality of crank case components having mating surfaces, through which the crank case is assembled, a crank shaft rotatably supported in the crank case at a portion between the mating surfaces of the crank case components, and a belt driven-type continuously variable transmission mechanism operatively connected to one end of the crank shaft through a clutch belt. The continuously variable transmission mechanism includes a drive shaft, and the clutch belt is stretched around the drive shaft and the crank shaft so that a tensioning direction of the clutch belt is shifted from a line passing the mating surfaces of the crank case components at a predetermined angle therebetween.

Abstract: A breather device of an engine is connected to an engine suction system. A breather chamber thereof for separating a blowby gas generated inside a crank chamber of the engine into gas and liquid is formed so as to face to a mating face of a plurality of cases, including a crankcase, connected to each other via a gasket, and a communication port is formed to the gasket, through which the blowby gas comes and goes in a space within the plurality of cases to thereby carry out the gas-liquid separation of the blowby gas. A cam chamber receiving a cam for driving a valve train provided for a cylinder head of the engine is arranged at a connection portion of the plurality cases including the crankcase in a sectioned manner in adjacent to the crank chamber in an axial direction of the crankshaft, and the breather chamber is formed above the cam chamber, the breather chamber being provided with a main opening so as to face to the cam chamber.

Abstract: A snowmobile provided with a water-cooling type engine has a body, half of which is covered by an engine hood so as to form an engine room therein. The water-cooling engine is transversely mounted in the engine room, and the engine includes a crank case, a cylinder block disposed above the crank case, a cylinder head disposed above the cylinder block, and a crank shaft rotatably supported in a manner inclined rearward. The cylinder head is covered by a head cover so that a mating surface thereof is inclined forward such that a front side of the cylinder head is lower, in level, than a rear side thereof.

Abstract: An all terrain vehicle has a rear structure in which a exhaust duct extends rearward from a rear portion of a belt transmission and is detachably supported by a vehicle body frame, the exhaust duct is composed of a plurality of constituent members coupled to one another along an exhaust direction of the exhaust air flowing in the exhaust duct, the constituent members having a distance from one another are formed from a high rigidity material maintaining its own shape thereof, and the constituent members are detachably coupled to one another through a coupling member formed of an elastic material.

Abstract: A scooter-type motorcycle has a structure in which an article accommodation box is disposed below a rider's seat which is upward openable, and a power unit including an engine and a power transmission is disposed below the article accommodation box to be vertically swingable together with a rear wheel. The power unit is connected to a swing shaft which is disposed above a front portion of an engine crank case, and a starter motor for starting an operation of the engine is disposed above a rear portion of the crank case. An air cleaner, a suction pipe, a throttle body and an intake manifold are arranged substantially horizontally from a rear side portion of a motorcycle body towards a front side portion thereof so as to constitute an engine intake device to be connected to the engine. The throttle body is disposed between the swing shaft and the starter motor.

Abstract: An all terrain vehicle for smoothly introducing an exhaust air from a radiator rearward and improving cooling performance for cooling respective members of the vehicle is provided with a front structure, in which a cooling fan is provided on a rear surface of the radiator so that a central portion of the cooling fan is offset from a center of the radiator toward a side opposite to a side on which the belt transmission is arranged, an exhaust pipe connected to a front portion of the cylinder assembly is provided to extend toward the side on which the belt transmission is arranged so that the exhaust pipe extends downward at a portion above the belt transmission, and the inlet duct is provided on the side on which the exhaust pipe is provided so as to vertically extend along the vehicle body frame provided vertically through a portion below the exhaust pipe.

Abstract: An outboard motor is provided with a four-stroke-cycle engine and an oil pan disposed below the engine. In the arrangement of the oil pan, a lubricating oil reservoir is arranged on a front side of the oil pan, and an exhaust gas passage and a cooling water passage are arranged on the rear side of the lubricating oil reservoir.