Common motorcycle faults

Fault analysis
Blue smoke from the exhaust pipe
The fault phenomenon of blue smoke is: during the operation of the engine, light blue smoke can often be seen at the tail of the exhaust muffler, and the oil is consumed too quickly. The cause of the fault may be: the oil level is too high; the cylinder compression pressure is lower than the specified value; the gap between the piston and the cylinder barrel increases.
Black smoke from the exhaust pipe
The fault phenomenon of black smoke is: when the engine is working, the exhaust pipe emits black smoke, and a pungent gasoline smell can be smelled, which is more obvious during acceleration. The cause of the fault may be: the mixture is too rich; the spark plug works poorly; the ignition is too late.
White smoke from the exhaust pipe
The original fault phenomenon of white smoke is: when the engine is working, white smoke comes out of the exhaust pipe. The cause of the fault may be: there is water in the fuel; there is water in the cylinder or muffler.
Troubleshooting
Blue smoke from the exhaust pipe
First check whether the oil level is too high, because a high oil level can easily cause the oil to rise. When checking the oil level, do not check it right after the engine is stopped, and check it again 10 minutes after stopping. If the oil level is too high, the excess oil should be released in time. If the oil level is normal, for engines that have been used for a long time, check the cylinder compression pressure and the possibility of increased clearance due to wear of the piston, piston ring and cylinder. The increased clearance causes the oil to rise. After inspection, if the cylinder pressure is lower than the specified value, further check whether the piston is stuck with carbon deposits, excessive wear or loss of elasticity. If the above situation occurs, the piston ring should be cleaned or replaced. For serious wear of the cylinder barrel and the clearance between the piston and the cylinder barrel exceeds the specified value, the cylinder should be bored and the piston should be replaced.
For engines that have just been overhauled or replaced with piston rings, the oil often rises due to the wrong installation of the inner and outer cuts (or cut corners) of the piston ring. If the above situation occurs, the piston ring should be reinstalled.