Fix Carburetor fuel over flow
In carburetors, fuel is filled in the carburetor bowl and then supplied to the jets. there is a set level that is maintained to assure a sufficient supply of fuel to the jets. and that level is adjusted by afloat. when the bowl is filled up the float raise and closes the valve that supplies the fuel and then as the fuel is consumed the fuel level drops with it the flot goes down and that opens the fuel valve again to replenish it.
Float Hight is too high: if the float height is too high that will raise the fuel level in the carburetor bowl. if it is raised too high then the fuel will leak into the engine uncontrollably thus causing a rich condition.
too hight float level can also cause fuel to flow from slow jet at wide open throttle. which is not normal.
normally when throttle is pulled beyond 25% the fuel level in float bowel drops which cuts off supply to the piolet jet and when throttle is released the fuel level increases that start back the fuel supply to piolet jet which cause the motorcycle to run at idle.
Float level is too low: if the float level is too low then on high speeds the carburetor bowl won't replenish enough to reach the main jet. this will cause sudden power drop or hick-ups at full throttle. and also if the float height is low then the engine will run leaner and the spark plug color will appear white.
Rule No.1: on most carburetors, the float height is set adjacent to the carburetor body. but float height varies from motorcycle to motorcycle. so always consult the service manual for guidance.
Rule No.2: place the carburetor on the side. float side facing right. then tilt the carburetor to the left at 45 degrees angle. most carburetors are adjusted on this angle because at this angle float is hanging free and you can adjust float height better from this angle.
before adjusting float tilt the carburetor to 45 degrees for proper adjustment. or look for the specific angle for your motorcycle carburetor in the service manual.
Float valve Seat
Float valve Position towards it's seat
there is a Groove on the upper side of the float valve for the float to settle
push the tab on the float to decrease the fuel height in carburetor bowel
lift the tab on the float to increase the fuel height in carburetor bowel
there is a dampner on the top of the float valve
adjust the float height where is touches the dampner pin
there is a line that is at the side of the float, for most carburetors that line is set parellel to the
consult your motorcycle service manual for the correct float height for your motorcycle
Float height set too low
Float height set too high
correct float height
correct float height