Application Study On Motorcycle Engine Using FAI System

Under the pressure of increasingly serious air pollution caused by emission worldwide, the issues of protecting environment and restricting exhaust have caught much more attention nowadays. In our country, the carburetor engine has faced the fate of being replaced by EFI engine. But conventional EFI has the disadvantages of the complex structure and high cost that can hardly be accepted by users. Compared with it, FAI EFI system has far more superiorities in structure, cost and performance etc, more suitable for the requirement of motorcycle EFI.FAI EFI motorcycle was researched thoughly in this thesis. First, the throttle body assembly was tested for its durability and reliability The test of fluid measure was performed as well. Second, the Oxygen Sensor was tested and developed in durability, reliability and was made a holistic layout. Third, FAI motorcycle was tested for the start problem in high temperature environment. The test results indicate that the throttle body assembly can meet the durability and reliability requirements of motorcycle. Forth, a new style of small-sized Oxygen Sensor customized for motorcycle had been developed and the setting of Oxygen Sensor was also tested and researched. The result shows that the Oxygen Sensor has good working reliability and being a good layout for motorcycle while installing it nearby the discharge valve on cylinder head. Fifth, a self bubble-out fuel feed system has been developed after a lot of researches and the start problem caused by bubbles from gasoline engine was solved thoroughly, especially in a high temperature environment.Moreover, the test to compare the external characteristic of FAI motorcycle and carburetor motorcycle, and the durable emission test of FAI motorcycle were carried out. The results indicate that the driving performance of FAI engine rising significantly at low and middle speed. Due to the close-loop feedback control technology, A/F (air/fuel) ratio is so stable and exact that the engine has a sufficient combustion and the fuel consumption is low. The test data of motorcycle emission indicate that performance of FAI motorcycle is very stable. The emission level can meet Europeanâ…¡standard and local restriction of Beijing without catalytic converter, and reach the requirement of emission durability over 10000km.