Mikuni carburetors, commonly installed on motorcycles ranging from small single cylinder dirt bikes to V-Twin motorcycles, have a plastic float to regulate fuel consumption. The float in the Mikuni carburetor sets the height of gasoline that rests inside the bowel. If you set the float too high, you risk overflowing gasoline from the carburetor and if you have it set too low, you risk running out of gas when you have your motorcycle at higher throttle positions. Mikuni has specific measurements for the setting the float levels.
Remove the four screws that hold the float bowel onto the bottom of the carburetor. Pull the float bowl and float bowl gasket off the carburetor. Use a Phillips screwdriver to remove the float bowel screws.
Place the carburetor upside down and let the float rest against the float needle. Do not touch the float at this time.