Abstract: The clutch control system includes a motor in a liquid pressure modulator for engagement/disengagement of a clutch, a clutch control unit for controlling the operation of the motor, vehicle condition detection means which detects at least that an engine is in working and which detects the running speed of the vehicle, and neutral detection means for detecting the neutral state of a transmission. As controlled states of the clutch, there are set a first control state in which the clutch is in a partially engaged state or an engaged state, and a second control state in which the clutch is disengaged. When the engine being working and the vehicle speed being in excess of a predetermined value is detected and the neutral state is detected, in the first control state, transition to the second control state is effected and the clutch is disengaged.

Abstract: A clutch operation mechanism wherein when a clutch is disengaged and engaged by manual operation or by operation of an actuator the one operation does not affect the other operation. The clutch operation mechanism includes a lever side lost mechanism which is disposed between a clutch lever and a turn-operating force transmitting member for interrupting, from the clutch lever side, an operated-force applied from the turn-operating force transmitting member by driving the electric motor when the clutch lever is not operated. A motor side lost mechanism is disposed between the electric motor and the turn-operating force transmitting member and interrupts, from the side of the electric motor, the operated-force applied from the turn-operating force transmitting member by operating the clutch lever when the electric motor is not operated.

Abstract: A clutch actuator device of a saddle-ride-type vehicle includes: a first master cylinder which is generating an oil pressure; a first release cylinder which is performing an engagement/disengagement operation of a clutch upon reception of the oil pressure transmitted from the first master cylinder by way of a first hydraulic pipe; and an actuator which is driving the first master cylinder in automatically performing the engagement/disengagement operation of the clutch. The clutch actuator device includes a seesaw member which constitutes a power transmission member for transmitting an operational force of a clutch lever or a drive force of the actuator to the first master cylinder, and a seesaw member rotational angle sensor which is detecting an operation quantity of the seesaw member.

Abstract: A change gear switch of a rod-shape handle bar equipped vehicle which allows a ride to easily manipulate a switch manipulation portion while grasping a grip portion and, at the same time, prevents a hand of a rides or a glove from interfering with a switch manipulation portion. Switch manipulation portion for the transmission manipulation are mounted on switch boxes which are arranged adjacent to grip portions of the handle. Manipulation face of the switch manipulation portions are arranged at position which are further toward an inside of the handle bar than where the grip portion are located. One of the manipulation faces is mounted further toward a front side of the vehicle than where the grip portion are located, and another manipulation face is mounted further toward a lower side than where the grip portions are located.

Abstract: A grip force of a driving wheel is maintained by identifying an actual condition of a motorcycle and controlling a clutch in a timely manner. A clutch control system includes a clutch, an actuator unit causing the clutch to engage or disengage, a rear wheel speed sensor, a front wheel speed sensor, a clutch lever sensor and a controller controlling a control motor based on a rear wheel speed and a front wheel speed. When the rear wheel speed is lower than the front wheel speed and an absolute value of a difference between the rear wheel speed and the front wheel speed is greater than a threshold value, the control motor is driven so as to reduce a transmission force of the clutch. When an operational amount of the clutch lever is greater than a threshold value, processing to reduce the transmission force of the clutch is suspended.

Abstract: A shift position changing drive member for a transmission includes an arm member capable of turning around the axis of a shift spindle for drivingly turning a shift drum in response to the turning of the shift spindle wherein the shift drum is prevented from coming into a neutral position even if the shifting speed is stopped in midstream. A lost motion spring includes gripping portions gripping a pressing portion from both sides of a coil portion surrounding the shift spindle. An arm member of shift position changing drive member is provided with a pressure-receiving member which is gripped by both gripping portions in such a manner that when the turning member is turned, if, in response to the turning direction, the pressing portion abuts against one of the gripping portions for turning, the other of the gripping portions abuts against the pressure-receiving member.

Abstract: A clutch hydraulic mechanism wherein the positional relationship between two cylinders is not varied, and a compact structure can be achieved. A see-saw member for transmitting motive power is provided between a second release cylinder and a first master cylinder and the first master cylinder and the second release cylinder are formed in the same cylinder block. This eliminates the need for adjusting the positions of the first master cylinder and the second release cylinder. In addition, it is possible to dispose the first master cylinder and the second release cylinder close to each other.

Abstract: A clutch hydraulic system for a vehicle wherein it is possible to independently operate two systems, to increase the degree of freedom in designing, and to achieve a reduction in cost. A seesaw member for transmitting motive power is provided between a second release cylinder and a first master cylinder, the first master cylinder and a second hydraulic oil pipe communicate with each other through a large diameter hole and a small diameter hole provided as communicating passages through which oil flows. A reservoir tank is provided for reserving the oil for controlling the amounts of the oil in the hydraulic oil passage on the side of the first master cylinder and the amount of the oil in the hydraulic oil passage on the side of the second release cylinder is connected to a second master cylinder.

Abstract: In a transmission for a vehicle including a shift drum rotatably supported by an engine case for selectively establishing multiple gear trains of respective speed steps in accordance with the rotational position of the shift drum, a shift-position changing-driving member is interlocked with and connected to an end portion of the shift drum so as to drive the shift drum to rotate. A shift-position sensor detects which of the multiple gear trains is established. The maintainability of the shift-position sensor is achieved by a transmitting mechanism that transmits the amount of rotational movement of a shift drum. The shift-position sensor is interlocked with and connected to an end portion of the shift drum. A shift-position sensor is disposed at and fixed to the outside of an engine case so as to detect the acting amount that is transmitted by the transmitting mechanism.

Abstract: A transmission is provided for changing gears by performing rotation control of a shift drum transmission between an internal combustion engine and a drive wheel by use of an actuator provided on one side of the shift drum and an intermittent feed mechanism driven by the actuator disposed on the other side of the shift drum.

Abstract: In a clutch manipulation assist device which includes a clutch assist actuator, the actuator is arranged at a position where it is possible to suppress the influence of heat from an engine on the actuator without requiring the heat insulation structure or the like. In a clutch manipulation assist device which includes a clutch mechanism 61 which is arranged in a power transmission path for transmitting a rotational driving force of an engine to a wheel, a clutch-manipulation mechanism in which a clutch manipulation force is inputted, and an actuator which generates a clutch assist force in response to a manipulation of the clutch manipulation mechanism, the actuator is arranged in front of the engine and outside a main frame.

Abstract: A speed change control device for a transmission of an internal combustion engine includes a driving means having an electric motor for rotatably driving a shift drum. The electric motor has a rotation axis orthogonal to an axis of a shift drum. A barrel cam having a cam groove rotates about an axis parallel to that of the electric motor. A transmission rotation member is interlocked and is coupled to the shift drum so as to be rotatable about the axis orthogonal to the rotation axis of the barrel cam. The transmission rotation member is provided with a plurality of engagement pins that selectively engages the cam groove. The resulting configuration allows the electric motor to be disposed inwardly with respect to an outermost side of the body of the internal combustion engine in the direction of the axis of a shift drum and improves the shift accuracy.

Abstract: A clutch device is configured to include a clutch mechanism, a clutch actuator operatively engaging and disengaging the clutch mechanism, a clutch lever, and an assist pressure generator which generates assist hydraulic pressure by driving an electric motor. The assist hydraulic pressure is supplied to the clutch actuator to operatively engage and disengage the clutch mechanism. The clutch device further includes a first turning angle sensor which detects the turn operation angle of the clutch lever, a control unit which controllably drives the electric motor based on the turning operation amount of the clutch lever and adjusts the driving force generating gain characteristic of the electric motor, and a gain adjustment knob which variably sets the gain characteristic. The clutch device makes it possible to changeably set the magnitude of an assist force of an assist device according to a rider's preference.

Abstract: To provide a control method for a power transmission device which can prevent the generation of impacts and noises when a speed change mechanism is changed over from a neutral state to a first speed gear without using a brake mechanism. In a control method of a power transmission device for controlling a power transmission device for transmitting a rotational power of a crankshaft of an internal combustion engine to an output side by way of a clutch mechanism and a speed change mechanism, the speed change mechanism is automatically changed over from a neutral state to a first speed gear during a period from a point in time Ts at which an ignition switch is turned on to a point in time at which an engine rotational speed arrives at a steady-state idling rotational speed Nid due to the starting of an internal combustion engine.

Abstract: A twin-clutch transmission wherein a center distance between input shafts and an auxiliary speed-change shaft can be shortened and the number of gears can be reduced. A twin-clutch transmission is provided which includes a first input shaft and a second input shaft, an auxiliary speed-change shaft, and a plurality of gear pairs. The first and second input shaft are connected, through a first clutch and a second clutch, respectively, to an input element, and disposed on the same axis. The auxiliary speed-change shaft is disposed parallel to the first and second input shafts. The plurality of gear pairs are provided between the first and second input shafts and the auxiliary speed-change shaft. An input path from the input element to the first clutch is different from that to the second clutch, and primary ratios of the input paths are set to values, respectively, different from each other.

Abstract: A change gear switch of a rod-shaped handle bar equipped vehicle which allows a rider to easily manipulate a switch manipulation portion while grasping a grip portion and, at the same time, prevents a hand of a rider or a glove from interfering with a switch manipulation portion. Switch manipulation portions for the transmission manipulation are mounted on switch boxes which are arranged adjacent to grip portions of the handle. Manipulation faces of the switch manipulation portions are arranged at positions which are further toward an inside of the handle bar than where the grip portions are located. One of the manipulation faces is mounted further toward a front side of the vehicle than where the grip portions are located, and another manipulation face is mounted further toward a lower side than where the grip portions are located.

Abstract: To reduce the axial size of a twin-clutch device including first and second clutch actuating mechanisms arranged in parallel along the axes of first and second driven shafts that are coaxial. A first clutch disconnection/connection control mechanism is provided for switching disconnection/connection of the first clutch actuating mechanism. A second clutch disconnection/connection control mechanism is provided for switching disconnection/connection of the second clutch actuating mechanism. A second clutch disconnection/connection control mechanism is arranged between first and second clutch inners so that at least a part of the second clutch disconnection/connection control mechanism is accommodated in at least one of first and second cylinder portions.

Abstract: A twin-clutch device includes first and second clutch actuating mechanisms; a first clutch disconnection/connection control mechanism for exerting on the first clutch actuating mechanism a controlling force for switching disconnection/connection of the first clutch actuating mechanism; and a second clutch disconnection/connection control mechanism for exerting on the second clutch actuating mechanism a controlling force for switching disconnection/connection of the second clutch actuating mechanism. The first and second clutch disconnection/connection control mechanisms include control actuating members that are supported on a fixing member in a non-rotating state while being allowed to move in a direction along rotation axes of a first driven rotary member and second driven rotary member, the control actuating members being respectively connected to first and second clutch actuating mechanisms via bearings.

Abstract: A transmission is provided for changing gears by performing rotation control of a shift drum transmission between an internal combustion engine and a drive wheel by use of an actuator provided on one side of the shift drum and an intermittent feed mechanism driven by the actuator disposed on the other side of the shift drum.

Abstract: A twin-clutch transmission wherein a center distance between input shafts and an auxiliary speed-change shaft can be shortened and the number of gears can be reduced. A twin-clutch transmission is provided which includes a first input shaft and a second input shaft, an auxiliary speed-change shaft, and a plurality of gear pairs. The first and second input shaft are connected, through a first clutch and a second clutch, respectively, to an input element, and disposed on the same axis. The auxiliary speed-change shaft is disposed parallel to the first and second input shafts. The plurality of gear pairs are provided between the first and second input shafts and the auxiliary speed-change shaft. An input path from the input element to the first clutch is different from that to the second clutch, and primary ratios of the input paths are set to values, respectively, different from each other.