针对某摩托车发动机中速性能较差的情况,运用发动机性能模拟分析软件GT-Power对该机进行性能开发,找出了原机中转速性能差的原因。通过优化进排气凸轮型线、空滤器结构、排气管管长和管径,提高了发动机的充气效率和发动机整机性能。对优化后的发动机进行了台架试验,优化后发动机的最大扭矩为10.13N.m,最大功率为8.03kW。 Aiming at the poor performance of a motorcycle engine at medium speed, the engine performance simulation software GT-Power was used to develop the performance of the engine, and the reasons for the poor performance of the engine speed were found out. By optimizing the intake and exhaust cam profile, air filter structure, exhaust pipe length and diameter, improve the engine’s air charge efficiency and engine performance. The optimized engine was tested on a bench. After optimization, the maximum torque of the engine was 10.13N.m and the maximum power was 8.03kW.