Research On Variable Intake System Of Motorcycle Engine

In order to improve engine performance and to develop the potential capacity of small engines, modern motorcycle engine starts to focus on multi-valve technology. However, the contradiction caused by the differences of power performance between engines at high-speed under heavy load and at low-speed under small load, and the contradiction between fuel economy and emissions performance become much more remarkable. All these problems can not be effectively solved just by increase or decrease the number of valves. What's more, the design of small and medium-sized engines is different from that of other engines because they are affected by the price and market situation, not to speak of the strict requirement of size arrangement.In this paper, TICERI (Tianjin Internal Combustion Engine Research Institute) new designed four-valve 125ml engine for Zhejiang Xingyue Group Co. Ltd. was used, to improve the engine performance under partial load, on the condition that without making any big changes, and keep maximum power and maximum torque maintain in the meantime. Considering these requirements which just mentioned and other factors such as installation, processing, production, lots of repeated researches were studied and compared, then the scheme of continuously variable intake channel cross-sectional area was chosen.Main contents include: establishment of the engine working-process model by using one-dimensional simulation software BOOST; model reliability certification; research on intake system scheme options; optimization of the design of intake system; final verification of the prototype of the software simulation and bench test; prospect and ideas of further development.The research results met the requirements. Together with theoretical analysis, this design, which can be used as a model to the development of other similar engines, is of certain reference value.