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Large motorcycles have a strong recreational aspect. Therefore, in addition to the sportiness that comes from the direct torque feel and the comfort that comes from the ease of operations, users demand improvements to fuel economy from the perspective of the environment and riding economics. In order to satisfy these needs, we have developed the world's first dual clutch transmission (hereinafter referred to as DCT) for motorcycles. In order to make the DCT more compact, we adopted a dual shaft construction for the main shaft, two hydraulic clutches arranged in-line, the basic structure of the gear shift mechanism carried over from a manual transmission (hereinafter referred to as MT) vehicle, a hydraulic circuit consolidated into the engine side cover, and shared use of engine oil for clutch actuation. Through these innovations, it became possible to carry over the die of the crankcase used on the MT vehicle as well as being able to load it onto the same frame as the MT vehicle.

The world's first Variable Cylinder Management (VCM) system for large motorcycles, which will achieve both high power and low fuel consumption, has been developed. The system uses a mass production in-line four-cylinder engine which has a displacement of 1137 cm₃ as the base engine. The VCM system is capable of increasing and decreasing the number of working cylinders between 2-cylinder, 3-cylinder and 4-cylinder operations by modifying some parts of the base engine. Utilizing throttle valves installed on each cylinder, the throttle valves for continuously operating the regularly working cylinders and the on-demand working cylinders are controlled by three motors, which divide them into three independent lines. In order to improve fuel consumption by reducing the pumping loss of the non-working cylinders, the engine is equipped with hydraulically operated intake and exhaust valve deactivating mechanisms.

The world’s first variable cylinder management system, VCM system, for large motorcycles has been developed. The system uses an in-line four-cylinder, 1 137 cm3 engine as the base, and allows changing of the number of working cylinders from 2-cylinder to 3-cylinder to 4-cylinder. To eliminate an abrupt change of power delivery when shifting number of working cylinders, the electronically-controlled throttle valve (Throttle-By-Wire: TBW) is employed. Coupled with the harmonized control of the intake-and-exhaust valve deactivating system, the smooth switching of number of working cylinders suitable for motorcycles has been realized. As a result, while maintaining the same power output characteristics of the conventional engine, EURO 3 exhaust emission regulations are satisfied while attaining approximately 46% better fuel economy in the New European Driving Cycle mode (NEDC mode).

There are various demands concerning the motorcycle rider’s throttle input such as nonlinearly engine output attribute control and maximum speed control. To realize those demands by electronic control, we mounted the Drive-by-Wire (DBW) throttle system, which is currently being used on existing automobiles, to motorcycles, but the system failed to meet the demands of the motorcycle. Response to the throttle speed change was an issue; therefore, we built up the control system to satisfy the motorcycle’s demand for response by changing the high speed response equation of adaptive sliding mode control and adding the hysteresis property correction equation of the throttle body drive-train. As a result, we could realize response equivalent to that of a mechanical throttle.