Benelli TNT 25 - Too Much Exhaust Smoke

Too much exhaust smoke:
White exhaust smoke:
Piston oil ring is worn;
Cylinder is worn;
Valve seal is damaged;
Valve guide is worn;
Oil level is too high
Black exhaust smoke:
Air filter is blocked
Brown exhaust smoke:
Vent pipe clamp is loosened;
Air filter has poor sealing or not assembled
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