Don dmi's low-speed abnormal sound

Cause analysis of abnormal sound in low speed feed of dmi in Tang dynasty;

1. The oil needs to be changed or the oil viscosity does not match.

2. Engine oil does not completely lubricate all parts of the engine.

3. The engine wear clearance becomes larger.

4. There is too much carbon deposit in the engine, throttle and spark plug.

5. The air filter is too dirty.