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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).

The government has been imposing a stricter diesel engine efficiency standard to reduce carbon dioxide, NOx and other particulate emissions. Diesel combustion improvement is a major concern, and many researchers have examined diesel combustion and its sprays. One possible method to solve the technical problems is applying the Variable Orifice Nozzle (VON) to fuel injection systems. The VON, which nozzle cross-sectional area is changed continuously, has been developed for direct injection (DI) diesel engines. The orifice changing mechanism is composed mainly of a rotary valve, drive shaft and small pulse motor. The VON's standard deviation (SD) of injection quantity in injection pump operation range is the same as the conventional hole nozzle's due to the rotary valve that is fixed by a spring. The smaller orifice of the VON has produced a higher injection pressure and produced a longer injection duration than that of a larger orifice.