What is the cause of motorcycle muffler ringing?

Check the following items one by one:

1, spark plug, change it or take it off and put it on the fire. After it turns red completely, it is naturally cooled to remove the carbon deposits on it.

2. carburetor. If the first step fails, go to the maintenance department to clean the carburetor.

This step should be done first. Check the gasoline for impurities (especially water).

4. Check whether the exhaust pipe is broken, if it is rusted, it is possible.

In many cases, it will cause the phenomenon of beating, including the uncoordinated oil-gas mixing ratio. I have encountered such a situation before, and I did it by adjusting the valve.