MOTORCYCLE HAVING ENGINE PHASE DECIDING SYSTEM

摘要

PROBLEM TO BE SOLVED: To perform proper ignition of a cylinder during first rotation of a crank shaft. SOLUTION: A system to decide the phase of an engine 64 comprises a crank gear sensor 132 situated in the vicinity of a crank gear 84; a pressure sensor 124 situated at a manifold 116; and a processor 128 communicating with the sensor. The crank gear teeth of first and second groups pass through the vicinity of the crank gear sensor before both of first and second pistons 92 and 96 do not reach TDC. The teeth of a third group pass the vicinity of the crank gear sensor before a first piston reaches TDC and after a second piston reaches TDC. In a case of low rpm, for example, during starting, a processor measures and compares a time in which the teeth of the group pass the vicinity of the crank gear sensor and decides an engine phase during single rotation of a crank shaft 80. At high rpm, the processor decides an engine phase by using a pressure sensor.