Abstract: A main shaft side sprocket wheel and a countershaft side sprocket wheel are provided for relative rotation on the shafts with a chain wrapped around and extended between the sprocket wheels. One of the driven gears is a floating gear provided for relative rotation on the countershaft. The countershaft side sprocket wheel is provided for integral rotation with the floating gear. The main shaft includes a main shaft inner shaft which includes the main shaft side sprocket wheel, and an outer pipe disposed coaxially on the outer side of the main shaft inner shaft in a diametrical direction and capable of being placed into and out of integral rotation with the main shaft side sprocket wheel. A reverse transmission gear for meshing with a driven gear is provided on the outer pipe. A reduction gear ratio by the floating gear or the reverse transmission gear is set higher than 1.

Abstract: A transmission for a vehicle is provided which prevents generation of a speed change shock at the time of starting the vehicle from a neutral condition. In the transmission, hydraulic clutches are each put into a connected state according to an action of an oil pressure, and a plurality of selectively engageable speed-stage gear trains are provided so that a neutral condition can be obtained. At the time of shifting from the neutral condition, where the oil pressures in hydraulic clutches are in a lowered state, to a starting condition in which a starting gear train is engaged, pressure in the hydraulic clutch corresponding to the starting gear train is controlled by a control valve, so that the oil pressure in the hydraulic clutch is maintained in the lowered state during and immediately after a shifting operation, and is subsequently increased in response to complete engagement of the starting gear train.

Abstract: A compact transmission device that alleviates shift shock and avoids engine stall at the time of deceleration. A discharge resistance changing unit changes discharge resistance of a clutch oil pressure on a side where a clutch is disconnected due to swapping of clutches in two stages. During a shift period where the clutch on a connection side is changed over from a disconnection state to a connection state, an invalid filling zone where a friction force is not generated on a clutch plate is provided. A control unit controls the discharge resistance changing unit at a time of the shift change such that the clutch on a disconnection side is brought into a state where a friction force is not generated after finishing a half clutch zone when the clutch on a connection side is in a half clutch zone after the invalid filling zone is finished.

Abstract: A solenoid body is attached to an outer surface side of a clutch cover attached to an engine main body so as to cover a pair of hydraulic clutches. A hydraulic control solenoid valve for controlling pressure of a hydraulic oil from an oil pump, a single switching valve for alternatively selecting hydraulic chambers of the pair of hydraulic clutches to be supplied with the hydraulic oil from the hydraulic control solenoid valve, and a shift solenoid valve for controlling operation of the switching valve are attached to the solenoid body.

Abstract: A power unit includes a transmission adapted to transmit rotational power from a crankshaft to a drive axle, with speed change. The transmission has an input shaft rotatably supported on a crankcase. A hydraulic clutch, configured to be selectively engaged and disengaged, is disposed coaxially with the input shaft. A clutch cover covering the hydraulic clutch is connected to the crankcase. A clutch actuator, which controls switching between engagement and disengagement of the hydraulic clutch, and an actuator cover, which covers the clutch actuator in a liquid-tight manner, are mounted to an outer surface of the clutch cover. An oil temperature sensor is mounted to the actuator cover, and is provided for detecting a temperature of oil in an oil chamber, formed between the clutch cover and the actuator cover.

Abstract: A transmission that reduces the difference of rotational speed when engaging a main shaft-side sprocket and a main shaft-outer shaft, in a low-speed traveling mode. When shifting from first gear to neutral in the transmission, a dog on a drive gear is engaged with a dog hole in a main shaft-side sprocket, engagement between a dog on a driven gear for first gear and a dog hole in a driven gear is released, and then a first clutch and a second clutch are disconnected with the drive gear and the main shaft-side sprocket being engaged.

Abstract: A braking force control apparatus in a motorcycle, includes a controller which controls a transmission to reduces driving force of an engine by a predetermined speed reduction ratio and transmits the driving force to a drive wheel of a vehicle, a clutch between the engine and the transmission, and brake devices which generate braking force on the wheels. The vehicle is switchable between a normal and a slow speed driving modes. In the slow speed mode the controller detects an inclination pitching angle ?, and causes the brake devices to generate braking force on at least one of the drive wheels when ??a predetermined value, then starts switching the clutch to a connected state when a driving operation is input, and gradually releases the braking force once driving force starts to be transmitted to the drive wheel.

Abstract: A braking force control apparatus for a saddle ride vehicle includes a transmission controller which reduces driving force of an engine by a predetermined speed reduction ratio and transmits the driving force to a drive wheel, a clutch device which connects—disconnects the driving force between the engine and the transmission, a brake device which generates braking force on the drive wheel, and a sensor which detects a state of the transmission. The transmission switches between a neutral state and an in-gear state, and when the sensor detects that the transmission is switching from the neutral state to the in-gear state, the controller causes the brake device to generate braking force on the drive wheel, and then releases the braking force upon completion of the switching to the in-gear state.

Abstract: A vehicle transmission includes a main transmission, a sub-transmission, a sub-transmission shift position sensor, and a map switching device. The main transmission is an automatic transmission configured to perform gear shifting according to a gear shift map selected between a first gear shift map and a second gear shift map in accordance with a throttle opening degree and a vehicle speed. The sub-transmission is configured to change rotational speed of rotational drive force output from the main transmission by manually selecting a sub-transmission gear position between a drive position and a low position having a reduction ratio larger than a reduction ratio of the drive position. The map switching device is configured to perform switching between the first gear shift map and the second gear shift map in accordance with sensing signals from the sub-transmission shift position sensor.

Abstract: A main shaft side sprocket wheel and a countershaft side sprocket wheel are provided for relative rotation on the shafts with a chain wrapped around and extended between the sprocket wheels. One of the driven gears is a floating gear provided for relative rotation on the countershaft. The countershaft side sprocket wheel is provided for integral rotation with the floating gear. The main shaft includes a main shaft inner shaft which includes the main shaft side sprocket wheel, and an outer pipe disposed coaxially on the outer side of the main shaft inner shaft in a diametrical direction and capable of being placed into and out of integral rotation with the main shaft side sprocket wheel. A reverse transmission gear for meshing with a driven gear is provided on the outer pipe. A reduction gear ratio by the floating gear or the reverse transmission gear is set higher than 1.

Abstract: A vehicle transmission includes a main transmission, a sub-transmission, a sub-transmission shift position sensor, and a map switching device. The main transmission is an automatic transmission configured to perform gear shifting according to a gear shift map selected between a first gear shift map and a second gear shift map in accordance with a throttle opening degree and a vehicle speed. The sub-transmission is configured to change rotational speed of rotational drive force output from the main transmission by manually selecting a sub-transmission gear position between a drive position and a low position having a reduction ratio larger than a reduction ratio of the drive position. The map switching device is configured to perform switching between the first gear shift map and the second gear shift map in accordance with sensing signals from the sub-transmission shift position sensor.

Abstract: A compact transmission device that alleviates shift shock and avoids engine stall at the time of deceleration. A discharge resistance changing unit changes discharge resistance of a clutch oil pressure on a side where a clutch is disconnected due to swapping of clutches in two stages. During a shift period where the clutch on a connection side is changed over from a disconnection state to a connection state, an invalid filling zone where a friction force is not generated on a clutch plate is provided. A control unit controls the discharge resistance changing unit at a time of the shift change such that the clutch on a disconnection side is brought into a state where a friction force is not generated after finishing a half clutch zone when the clutch on a connection side is in a half clutch zone after the invalid filling zone is finished.

Abstract: A solenoid body is attached to an outer surface side of a clutch cover attached to an engine main body so as to cover a pair of hydraulic clutches. A hydraulic control solenoid valve for controlling pressure of a hydraulic oil from an oil pump, a single switching valve for alternatively selecting hydraulic chambers of the pair of hydraulic clutches to be supplied with the hydraulic oil from the hydraulic control solenoid valve, and a shift solenoid valve for controlling operation of the switching valve are attached to the solenoid body.

Abstract: Shift controlling apparatus for a vehicle which automatically carries out changeover between a plurality of shift gear stages based on an automatic shift map including a drive mode shift map and a sport mode shift map having an increased region in which a speed change ratio is low compared to the drive mode shift map and corresponds to more sporty operation than that of the drive mode shift map. The drive mode shift map has a first mode portion and a second mode portion having an increased region in which the change gear ratio is low compared to the first mode portion, but smaller than the increased region of the sport mode shift map. Changeover between the first and second mode portions is carried out based on an acceleration history in accordance with a throttle opening of the vehicle.

Abstract: Shift controlling apparatus for a vehicle which automatically carries out changeover between a plurality of shift gear stages based on an automatic shift map including a drive mode shift map and a sport mode shift map having an increased region in which a speed change ratio is low compared to the drive mode shift map and corresponds to more sporty operation than that of the drive mode shift map. The drive mode shift map has a first mode portion and a second mode portion having an increased region in which the change gear ratio is low compared to the first mode portion, but smaller than the increased region of the sport mode shift map. Changeover between the first and second mode portions is carried out based on an acceleration history in accordance with a throttle opening of the vehicle.

Abstract: A shift controller with a first clutch CL1 that connects/disconnects the torque to a first main shaft and a second clutch CL2 connects/disconnects the torque to a second main shaft. A transmission is configured so that dog clutches DC1, DC2 for first speed and for second speed are engaged in a predetermined turned position P1-2 of a shift drum. A linear solenoid valve that supplies clutch oil pressure, a shift solenoid that switches a destination of the supply oil pressure between both clutches and a controller that controls the supply oil pressure and the turning of the shift drum are provided. The controller supplies predetermined oil pressure P1 to the CL2 in neutral, switches the destination of supply oil pressure to the CL1 when the shift drum is turned to P1-2 according to a shift instruction to engage gears and supplies maximum oil pressure P3 to the CL1 in predetermined time ta.

Abstract: A shift controller for a motor vehicle includes an electric motor configured to rotate a shift drum associated with a transmission. An oil temperature sensor is configured to detect temperature of lubricating oil for the transmission. A controller is configured to control the electric motor. The controller controls the electric motor to operate in a preset first motor duty until a first predetermined time elapses after operation of the electric motor is started when the shift drum is turned from a first predetermined position to a second predetermined position. The controller is also configured to operate the electric motor in a second motor duty calculated based upon oil temperature after the first predetermined time elapses.

Abstract: A reverse inhibitor mechanism for a transmission of an all terrain vehicle, in which a shift drum is jounalled to a side wall opposite the transmission case so as to be rotatably supported thereon, and a reverse inhibitor arm is detachably engaged with the reverse inhibitor groove formed in the outer circumferential surface of the shift drum to regulate a reverse setting. A reverse inhibitor shaft having the reverse inhibitor arm supported at one end thereof is positioned within the transmission case. The other end of the reverse inhibitor shaft is rotatably journaled to one of the opposite side walls of the transmission case from the inside of the transmission case. A distal end of the reverse inhibitor arm which swings by the rotation of the reverse inhibitor shaft is brought into engagement with the reverse inhibitor groove during assembly of the reverse inhibitor mechanism.

Abstract: In a clutch device wherein a plurality of clutch plates are relatively non-rotatably engaged with a clutch outer, a plurality of clutch disks disposed alternately with the clutch plates are relatively non-rotatably engaged with a clutch inner, and an end plate disposed so that the clutch plates and the clutch disks are disposed between itself and a piston slidably fitted in the clutch outer is relatively non-rotatably and axially movably supported on the clutch outer in the manner of being restricted in movement toward one end side in the axial direction, to prevent the clutch inner from coming out of position at the time of assembling the clutch device into position, thereby to enhance workability in the assembling operation, and to prevent the clutch inner from generating a collision sound by colliding against other member than the component members of the clutch device when the clutch is disengaged.

Abstract: A transmission for a vehicle in which changing a shift position is achieved by sliding a shifter. In sliding the shifter to change the established condition of gear trains respectively corresponding to a plurality of shift positions, the transmission of power from an engine to a main shaft is cut off. A feed mechanism for sliding the shifter is configured to reduce the sliding speed of the shifter in a neutral condition, or to cause the sliding operation of the shifter to have a single stopping action in the neutral condition during the sliding operation of the shifter in changing the established condition of the gear trains. The resulting configuration reduces the engagement noise when changing the shift position.