Abstract:
In a single-cylinder internal combustion engine fitted with a knock sensor, a temperature increase of the knock sensor is suppressed and prevented, and the reliability of the knock sensor is improved. The engine includes a crankcase, a cylinder block connected to the crankcase, a cylinder head connected to the cylinder block, a sensor mounting boss provided on the cylinder block, and a knock sensor mounted to the boss. Fins are provided on the cylinder block and the cylinder head. A heat insulation member is provided between the boss and the knock sensor.
Abstract:
A cam face 81 and a cam face 181 are formed in such a manner that an angular velocity ω represented by the following equation increases when a parameter R increases and the angular velocity ω decreases when the parameter R decreases, ω2=(1/m)·[F(tan α+tan β)/R], where the mass of the centrifugal weight (41) is m, the revolution radius that is the distance from the rotation center (0) of the centrifugal weight (41) to the center of gravity of the centrifugal weight (41) is R, the angle formed by a radial line (L0) and a tangent line (L1) of a point of the cam face (81) being in contact with the centrifugal weight (41) is α, the angle formed by a radial line (L0) and a tangent line (L2) of a point in the cam face (181) being in contact with the centrifugal weight (41) is β, and the urging force of a Belleville spring that urges a roller retainer (78) is F.
Abstract:
A friction plate (131) rotates in association with rotation of a pressure plate (77). A first pressing plate (132) presses the friction plate (131) to the right to move the pressure plate (77) to the right. A second pressing plate (133) receives a torque of the pressure plate (77) via the friction plate (131). A slide shaft (231) rotates together with the second pressing plate (133). The operation assist mechanism (220) gives a rightward force to the pressure plate (77), by the slide shaft (231) moving to the right upon receiving the torque from the second pressing plate (133). Balls (135) transmit a portion of the rightward force of the short push rod (43a) to the slide shaft (231) without use of the friction plate (131).
Abstract:
A centrifugal clutch for a vehicle includes a clutch housing having friction plates, a clutch boss having clutch plates, a pressure plate, and roller weights that press the pressure plate in a direction such that the friction plates and the clutch plates are brought into frictional contact with each other when the roller weights receive a centrifugal force. The vehicle power unit includes a main shaft which has an oil supply passage formed therein. The clutch includes a first oil supply path that supplies oil via the oil supply passage to the friction and clutch plates. The clutch includes a second oil supply path that supplies oil via the oil supply passage to the roller weights. The first and second oil supply paths are formed individually to allow independent adjustment of oil supply to each path.
Abstract:
A single-cylinder internal combustion engine includes a knock sensor mounted to apart other than a cylinder block to detect knocking. The engine includes a crankcase, a cylinder block, and a cylinder head connected by a bolt. A boss to mount the knock sensor is provided on the crankcase. A center of the boss is positioned on a same side of a cylinder axis as the bolt, when viewed in an axial direction of the boss.
Abstract:
A centrifugal clutch of a motorcycle has clutch housing which includes a friction plate, a clutch boss including a clutch plate, a pressure plate that pressure-contacts the friction plate with the clutch plate, a roller weight that receives a centrifugal force and presses the pressure plate toward a plate group side. The centrifugal clutch also includes an elastic body that constantly biases the pressure plate toward the plate group side to transmit a portion of a driving force from the clutch housing to the clutch boss even when the motorcycle engine is in an idling state. The elastic body may comprise a disc spring that biases the pressure plate toward the plate group and a coil spring that biases the pressure plate away from the plate group.
Abstract:
A friction clutch includes clutch housing having a friction plate, a clutch boss having a clutch plate, a pressure plate, a sub clutch, and a power-assist mechanism. The power-assist mechanism receives torque from the pressure plate when the clutch is disengaged and converts the torque into a force for moving the pressure plate in a direction which separates the pressure plate from a plate group. A cam surface, which supports and guides one or more roller weights, is formed on the pressure plate. The one or more roller weights move outward in a radial direction by a movement amount according to the magnitude of centrifugal force and press the pressure plate toward the plate group with force according to the movement amount.
Abstract:
According to some preferred embodiments, a clutch housing (46) of a clutch (2) has a bottom portion (46a) in a closed-end cylindrical shape, a plurality of arms (46d) extending along an axial direction from the bottom portion (46a) and provided along a circumferential direction centering on an axial center (C) of the clutch shaft (33), and a plurality of gaps (46e) formed between adjacent arms (46d). Off-springs (71) are arranged in the gaps and extend along the axial direction.
Abstract:
A friction clutch has a clutch housing including a friction plate, a clutch boss including a clutch plate, and a pressure plate causing the friction plate and the clutch plate to contact each other by moving in a predetermined direction. A clutch spring applies a biasing force in a direction of causing the pressure plate to press the friction and clutch plates into contact with each other. An annular retainer receives a reaction force to the biasing force of the clutch spring by supporting one end of the clutch spring opposite to the pressure plate. A circlip of a notched ring shape is fitted into an inner peripheral side of the clutch housing. The circlip locks the retainer to the clutch housing by abutting on an opposite side of the retainer. The retainer is configured to suppress radially inward deformation of the circlip when a vehicle engine is driven.
Abstract:
A motorcycle has a cylinder bore that is vertically offset from a crankshaft. A camshaft also is vertically offset from the cylinder bore. The offsets decrease the vertical dimension of the engine. An air induction system approaches a cylinder head from the rear to limit the degree to which the induction system extends forward of the engine. By decreasing the envelope of the engine, more space is provided on the scooter-type motorcycle for a foot rest forward of the engine and a storage compartment above the engine.