摩托车发动机出现冷车难以启动和动力不足时,通常都采用检查气缸压缩压力的方法来判断是气门与气门座,还是活塞、活塞环与气缸处出现了异常,但对于判断等真空式化油器节气门处的真空度、进气管与化油器及气缸盖间的密封是否正常,这种方法就不太准确了。实践证明,上述故障有相当一部分是由于发动机负压不足造成的,需要负 Motorcycle engine is difficult to start the cold car and lack of power, the pressure is usually used to check the cylinder compression method to determine the valve and valve seat, or piston, piston ring and cylinder at the exception, but for judging the vacuum oil The throttle at the vacuum, intake pipe and carburetor and cylinder head seal between the normal, this method is not accurate. Practice has proved that a considerable part of the above failure is due to lack of negative pressure in the engine, you need negative