Motorcycles can become unstable when operating at high speeds and at high cornering levels. For example, they can exhibit an oscillation at the rear wheel commonly known as “weave.” A system and method is provided which utilizes a high-fidelity computer simulation model of a 2- or 3-wheel motorcycle to predict operating states such as yaw rate, lateral acceleration and roll angle for a stable motorcycle at a given speed and steer angle. The operating state of a physical motorcycle can be measured and compared to that of the model at every instant in time to determine if the operating state of the physical motorcycle differs from that of the simulation model in such a way as to indicate loss of stability. The nature of that difference can then be used to intervene in the operation of the motorcycle independent of driver actions by application of brakes, modulating the engine torque or applying torques to urge the steering system in a corrective direction. Thus by comparing the physical response of the motorcycle to that of the computer model in an on-board controller these interventions can be applied at a time and intensity to stabilize the motorcycle and prevent a loss of control.

A motorcycle wheel is provided, in particular a motorcycle wheel suitable for use on an enduro motorcycle. The wheel includes a cast or forged rim having integrally spokes which extend toward a central hub connection region. The central hub connection region is configured to receive a hub element in a detachably fastened manner. The hub element forms a hub of the motorcycle wheel which is connectable to a motorcycle.

A variable speed control system includes a multiple-speed transmission which changes a speed of an engine output in multiple stages based on a change in meshing state of a dog clutch which is caused in association with an operation of a change pedal connected mechanically, a pedal load detection device which detects an operation load of the change pedal, and a control unit which suppresses or shuts off an engine output to the multiple-speed transmission and permits a speed change action of the multiple-speed transmission by the change pedal when a detected pedal load exceeds a pedal load threshold. The variable speed control system further includes an engine revolution speed detection sensor which detects an engine revolution speed. The control unit changes the pedal load threshold according to the engine revolution speed detected. Such variable speed control system can realize a stable speed change action irrespective of running conditions.

A shift fork shaft 123 has both end portions movably fitted in shaft supports 83e and 116a of a gear transmission 82. Clearances are left between bottom surfaces 83g and 116c of the shaft supports 83e and 116a and both end faces 123c of the shift fork shaft 123. Caps 145 are mounted in both axial ends of the shift fork shaft 123.

A cam-type damper 118 includes a drive cam 131 provided on a clutch shaft 114 without capability of relative rotation and a driven cam 132 provided on a main shaft 103 without capability of relative rotation. The clutch shaft 114 contains a shaft end of the main shaft 103 and the main shaft 103 is rotatably supported on the inner circumferential surface of the clutch shaft 114. The driven cam 132 provided on the main shaft 103 is disposed between a front end surface 114g of the clutch shaft 114 and a rear end surface 103h of a main shaft gear 103d provided on the main shaft 103 and the movement of the driven cam 132 in the axial direction is restricted.

A transmission case 210 supports a shift shaft 222 that constitutes a part of a speed change operation mechanism 220, and which receives an operating input and transmits a speed change motion of a transmission 201. A part of a transmission holder 162M in which part the shift shaft 222 is disposed includes a shaft insertion opening portion 162g that the shift shaft 222 is disposed so as to pass through.

A motorcycle includes an internal combustion engine, a frame, a fuel tank for carrying a fuel to be consumed by the internal combustion engine, and a container connected to the internal combustion engine and the fuel tank. The container is configured to store fuel evaporating from the fuel tank, and the container in a position of use is at least partially covered by the fuel tank. The fuel tank is supported pivotably relative to the frame between a maintenance position and the position of use.

A bicycle includes an electrical auxiliary drive, including an electric motor, a battery for storing electrical energy, which battery is connected to the electric motor, a crank mechanism having pedal cranks, which are mounted on a pedal crankshaft disposed about a crank axis, so as to be able to rotate, and a planetary gear for driving the bicycle both by the electric motor and by the muscle power of a driver, the planetary gear and the electric motor being disposed about the pedal crankshaft of the crank mechanism.

There is provided a two-wheeled vehicle overturn prevention method, wherein maximum allowable lean angles corresponding to vehicle body velocities are preset in relation to lean angles of a vehicle body, and in a case where an actual lean angle of the vehicle body exceeds a maximum allowable lean angle corresponding to an actual vehicle body velocity of the vehicle body or in a case where an estimated lean angle of the vehicle body after a predetermined amount of time exceeds or looks to exceed a maximum allowable lean angle corresponding to an estimated vehicle body velocity, the two-wheeled vehicle overturn prevention method is adapted to accelerate the vehicle body or keep the vehicle body from decelerating.

An electric vehicle (10) comprising: a frame (11); an electric battery module (24) comprising at least one battery connected to the frame; an electric motor (20) receiving power from the battery module (24); a transmission system (80) provided with a transmission casing (208B); said electric motor (20) is closely coupled to the transmission system (80) and is mounted on the transmission casing (208B); and a rear wheel (84) receiving power from the electric motor (20) through the transmission system (80) and said rear wheel (84) is connected to the frame using a rear suspension system; wherein the rear wheel (84) is connected to the frame (11) using said casing (208B) forming a part of the rear suspension system.