五羊WY125型摩托车采用四冲程发动机,由于四冲程发动机工作过程中燃用的是纯汽油,排出的废气中没有机油,排气管中也就没有机油沉积。发动机工作时,排气管温度较高,停车后(或发动机开始启动时的几分钟),由于排气管内外温差较大,空气中的水蒸汽便在排气管内壁凝结。一方面,凝结的水会使 Wuyang WY125 motorcycle with a four-stroke engine, because the four-stroke engine is burned during the work is pure gasoline, exhaust gas is not discharged, there will be no oil in the exhaust pipe deposition. Engine work, the exhaust pipe temperature is high, after stopping (or when the engine starts to start a few minutes), due to large temperature difference between inside and outside the exhaust pipe, the water vapor in the air condensation in the exhaust pipe wall. On the one hand, the condensation of water will make