1. The engine overheats due to prolonged overload or working at high power.
Therefore, users in the use of motorcycles, should avoid overweight, avoid long time in bad road or low block driving, do not drive at high speed in high temperature areas or high-speed running in place for a long time.
2.The engine overheated due to poor heat dissipation.
The causes of this situation, such as cylinder, cylinder cover with marl, oil pollution cover; Still have a kind of circumstance is, the motorcycle that has air-cooled engine, although the engine runs in high speed when clutch skid, but the speed is not high, cause cooling ability to reduce greatly.
In this regard, should be timely clean up the oil sludge, adjust or replace the clutch friction plate. As a result of clutch skid causes the engine to overheat, will appear in the motorcycle drive the following phenomenon: when the motorcycle starts, will clutch hold the handle to loosen, the engine speed increases, but the car moves forward slowly; In the uphill throttle, if the engine speed increases, but the power is significantly lower than usual, that engine overheating is caused by the clutch slip.
3. Overheating due to improper fuel mixing ratio.
When there is too little lubricating oil for gasoline engine, all kinds of friction parts will not get good lubrication, and the wear of machine parts will accelerate, causing the cylinder temperature to rise sharply. When excessive lubricating oil in its fuel, insufficient combustion leads to increased carbon accumulation, resulting in poor heat dissipation performance and increased engine temperature. Find these conditions should be replaced fuel oil or lubrication pump adjustment.
4. Overheating due to improper use of gasoline.
If the octane number is too low or stored for too long and the deterioration of gasoline, it will cause the engine detonation combustion, resulting in the working temperature within the cylinder rise, resulting in overheating of the engine. When checking the engine fuel system and ignition system are normal, the test can be conducted by replacing the new gasoline, if the overheating phenomenon disappears, then the gasoline is not suitable for use.
5. Overheating due to improper mixture concentration.
When the mixture is too thin, when burning in the cylinder, the flame propagation speed slows down, resulting in the combustion process is too long, the cylinder temperature rises; When the mixture is too thick, the combustion is inadequate, causing detonation and carbon deposition, and the cylinder temperature will rise. In view of the above situation, the carburetor should be adjusted in time.
6. Overheating due to ignition too early or too late.
The ignition time is too early, the combustion time is prolonged, causes the cylinder and the cylinder cover to be heated the time to be prolonged and causes the engine to overheat; Ignition time is too late, burning late, making the exhaust temperature higher and causing the engine to overheat.
7. Overheating due to carbon accumulation blockage of muffler.
If the muffler carbon accumulation is serious, exhaust gas is blocked, which leads to the increase of engine working load and overheating, carbon accumulation should be removed in time.
8.Overheating due to too high compression ratio.
When the combustion chamber carbon accumulation is serious or the cylinder cover pad is too thin will reduce the cylinder volume, compression ratio increases, thus causing overheating of the engine. To this end, the carbon accumulation should be removed or replacement cylinder pad.
Attention must be paid to, when the overheating engine after the cease-fire, in order to prevent sticking cylinder, the driver must pedal on the start lever more than 10 times (such as start action), but do not open the main power switch, when the engine feels easy to run, it shows that has eliminated the hidden danger of sticking cylinder.