Experimental Investigations On The Emissions Durability Of Motorcycles With EFI

Energy and the environment are the two main themes of social in the 21st century. The production of motorcycles has exceeded 25 million per year, which accounts for more than half of the world output. Therefore, in order to reduce emissions and meet increasingly stringent emissions regulations, the motorcycle scientific researchers should seek actively measures to reduce emissions. And then the motorcycle industry will scale new heights.To meet the 3rd emissions regulations of our country, researches on the following aspects in this article:1. Optimized the hardware of the engine electronic control system successfully. Designed and developed the throttle body and the pump components. Designed the driver circuit of the idle bypass valve and the carbon monoxide tank.2. Designed the control strategy of the idle bypass valve which meet the request of the engine idle and warming states. Established the different air-fuel ratio control strategies based on the different conditions of engine.3. Based on the CAN, designed and developed the integrated calibration which achieves four main functions: real-time parameters acquisition and display, on-line parameters editing, data saving and data playback .4. Calibration experimental investigation has been completed on a 125 ml single-cylinder four-stroke spark ignition engine. Researches on the flow characteristics and the dynamic response performence of the fuel injector were achived. It provided a prerequisite to the precise control of the air-fuel ratio. Determined the installation positions of TWC and oxygen sensor by measuring exhaust temperatures of the engine.5. A large number of studies on the vehicle calibration and emissions durability testing were finished. Put focus on the two factors impacting emissions durability. One is the drift issues of oxygen sensor, we developed and designed the self-learning control strategy of oxygen sensor; the other one is the problem of the three-way catalyst aging. The use of rare earth with high-performance oxygen storage materials and high temperature and high surface area, which reduced greatly the cost, increased the activity of a catalyst, extended the service life and achieved the emission durability test. Reached the third emission standards of our country .6.After 12000 km emissions durability assessment of the improved motorcycle with EFI, emission test results showed that HC emissions accounted for only about 40%, CO emissions accounted for only about 50 percent, and NOx emissions accounted for 78.7 percent of the emission standards,The results meet emission limits and motorcycle measurement method (GB14622-2007) requirements.