Development of a 150cc, 4-Valve CVT Engine for Future Emission and Noise Limits

A complete vehicle including engine has been developed with the main aims of fulfilling future noise and pollutant emission limits but also to satisfy customers demands in terms of comfort and low NVH level and good fuel economy. The engine layout and design features are discussed with the thermodynamic calculation and the optimisation of ports and the variable intake system. The modal analysis of the engine parts and the simulation of the surface vibrations shows the effect of acoustic measures and the obtained results. Ancillaries like CVT drive, double link lever engine mount, water cooling system, lubrication system, exhaust system with catalyst and secondary air are discussed. Characteristic diagrams and driving cycle emission show the achieved performance, low emissions and fuel economy.