In many cases of the development of motorcycle engines, the combustion analysis has been of the engine in laboratory, not of the one onto actual motorcycles. It is mainly because the combustion analyzer in the market is too large to load onto a motorcycle. Pressure sensor, crank angle detector, arithmetic unit and data record device are necessary to analyze the combustion. The arithmetic unit is to process detected signals and generally needs the largest space among them. Needless to say, more reliable results of the combustion analysis could not be obtained under such limited experimental conditions.
Therefore, we developed a compact combustion analyzer, which is possible to be loaded onto a motorcycle. The width of the arithmetic unit is 91mm, the depth 98mm and the thickness 20mm. The core chip has the calculation ability of 78MIPS at a clock speed 60MHz, and it has AD converter, DA converter and high-speed counter. With this hardware power, the analyzer can calculate maximum pressure and IMEP of every cycle as well as crank angle at the moment of maximum pressure, and output them.
This report addresses the developed compact combustion analyzer. First, the specifications of our analyzer are introduced with the general background of the combustion analyzer. Next, the analysis data, such as pressure and IMEP, are shown. These were obtained by this analyzer while the motorcycle actually running. It is confirmed that this analyzer provided valid results when loaded onto a 4-Cylinder 4-Stroke Engine in the condition of running either steadily or transiently.