Float Leaking

Hey guys, having a bit of trouble with my BSR42 CV carb. My float is leaking but I can't figure out why.


If the bike is upright it doesn't leak, but when I put it on the kickstand, gas slowly dribbles out the bottom drain.


When I have the carb off the bike and fill the fuel line with water, to test the float, I can tilt it 45 degrees in any direction and it doesn't leak, it is very reliable.


I'm totally confused how the float could pass the water test but still leak gas.


To make things more interesting, I have three different BSR42 carbs on my bench and have changed the float, float needle, float seat, float seat o-ring, everything I could think of, and this one carb still has problems.


I've already exhausted all the "obvious" items, can anyone think of any other reason it might be leaking?

Your float height is too high, if the overflow sees gas at 15 degrees,

Gas is thinner than water, so never test with water.

It was still leaking even with the float height set 3/16" below the top of the bowl.


I looped the drain line up and rode it around for a while and it stopped leaking, my latest theory is that maybe I had some debris in the tank which was causing it to leak a bit.

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