How is float measured?
Although not as accurate as a measuring device such as a flume or a flow probe, the float method can provide an educated estimate. Briefly put, this method involves measuring the surface velocity of the water with a floating object, and then multiplying this velocity by the width and average depth of the channel.
Why do carburetors need a float?
Because the carburetor can’t use fuel under pressure, whether delivered by a fuel pump or gravity, the float chamber is kept at atmospheric pressure. The carburetor float needle, moved by the float, controls fuel flow, maintaining the fuel level in the chamber.
What does the float do on a Mikuni carburetor?
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.
How to check the fuel level in a Mikuni fuel tank?
But some Mikunis can reveal the fuel height while on the bike. That is what you are doing with the clear tubing. That is not an overflow hole, as it is at the bottom of the bowl. At least the hole to use is at the bottom of the bowl. With the plastic tube in place, you unscrew the screw next to it and can check the level.
How do you measure float height on a Mikuni VM?
I tune a lot of Mikuni’s, but HSR’s not VM’s. Generally, the float height measurement is going to be the height of the float arm or float itself as measured from the arm, or the bottom of the float, to the surface where the bowl attaches.
What kind of needle does Mikuni use?
Mikuni uses two types of needles. One needle is a corrosion-resistant steel alloy, the other has a Viton rubber coating over the tip of a steel needle. Viton is a chemical-resistant, synthetic rubber, fluoropolymer. Both do a good job of sealing.