The carburetor is an important part of the motorcycle.The plunger-type carburetor float chamber uses a needle valve and a float to control an automatic oil intake system.There is a hinged structure between the fuel float and the carburetor seat.The fuel height of the float chamber decreases with fuel consumption.The float drives the float tongue and the fuel needle valve to move downward,so that the fuel needle valve opens and the fuel flows into the float chamber.When the amount of fuel flowing into the float chamber is less than the fuel consumption of the engine,the needle valve seat is in an open state,and the fuel flows into the float chamber.When the fuel height in the float chamber rises to the set height of the float,the fuel float rises under the action of buoyancy and drives the float tongue and the needle valve to move upward.The needle valve and the valve seat form a sealed working surface to prevent fuel from continuing to enter the carburetor float Chamber,so that the oil level of the carburetor float chamber is within the set value range.The height of the carburetor float is the key to the compatibility of the carburetor and the engine.

　　The quality of the plunger carburetor and the matching of the engine determine the performance and fuel economy of the motorcycle.The matching of the carburetor and the engine can be achieved by re-adjusting the carburetor,so that the performance of the engine under various working conditions can reach the best state,and the fuel economy of the motorcycle can be improved.

　　The poor matching between the carburetor and the engine is mainly manifested in:after the motorcycle runs through the running-in period,the carburetor choke valve still needs to be closed frequently when the hot car starts;the engine overheats during normal driving;the motorcycle has a frustration when driving at high speed Phenomenon:Incomplete combustion of mixed gas,poor power performance of motorcycles,serious carbon deposits in spark plugs,black smoke from exhaust pipes,reduced power,and weak acceleration;fuel consumption exceeds the standard,and fuel economy is poor.

　　The oil level of the carburetor float chamber is too low,the combustible mixture entering the engine is too thin,the distance between gasoline molecules becomes larger,and the combustion speed of the mixture slows down.Most of the heat generated by combustion is absorbed by the engine cylinder,piston,and lever head.Causes the engine temperature to rise and the engine overheats.Overheating of the engine reduces the performance of the lubricating oil,accelerates the wear of parts,and shortens the service life of the motorcycle.The oil level in the float chamber of the carburetor is too high,the fuel atomization becomes poor,the combustible mixture is too thick,and the mixture cannot be completely burned.A large amount of carbon deposits are generated between the combustion chamber,the top of the piston,the piston ring groove,and the spark plug electrode.The carbon deposit reduces the volume of the combustion chamber and changes the compression ratio of the engine;the carbon deposit and high temperature make the crankcase lubricating oil deteriorate.The engine accelerates the wear of the piston ring and cylinder block due to poor lubrication;if the combustible mixture is too thick,the mixture will burn completely,resulting in a decrease in motorcycle power and fuel consumption;if the combustible mixture is too thick,the mixture will burn.Complete combustion makes motorcycle exhaust pollutants exceed the standard.