What are the two pipes under the carburetor of motorcycle for?

The pipe at the bottom of carburetor is both an oil drain pipe and an overflow pipe. When the oil level in the carburetor is too high, gasoline will flow out of the pipe.

The oil leakage in the overflow pipe of motorcycle carburetor is mainly due to the displacement of the float in the float chamber, which makes the float needle valve unable to rise in place and completely closes the oil inlet hole. The gasoline that keeps entering will flow out of the oil leakage pipe.

The overall specific gravity of the float is lighter than that of gasoline, including foam and hollow float. Generally, it can be repaired after simple adjustment. If the float is damaged, replace it as much as possible. If the float cannot be replaced, only the whole carburetor can be replaced.

Extended data

principle of operation

Motorcycle oiler looks very complicated, but as long as you master some principles, you can adjust the motorcycle to the best condition. All carburetors work under the basic principle of atmospheric pressure.

Atmospheric pressure is a powerful force that exerts pressure on everything. Slightly different, but usually there is a pressure of 15 pounds per square inch. This means that the atmospheric pressure is 0/5 pound per square inch/kloc. By changing the atmospheric pressure in the engine and carburetor, the pressure can be changed and fuel and air can flow through the carburetor.

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