Bonneville America Forums Forums Technical Forums General Tech Engine Probleim with Air Mixture Screw

I was adjusting my air mixture today, and have ran into a problem. The left carb doesn't make a noticeable change except when completely turned in. I took the plug wire off the oppisite cylinder to adjust the carb. The right side worked fine and tuned right up. What can this be?

Maybe the left float is out of adjustment a letting a bit of fuel flood through the pilot while it's on the sidestand. This assumes you know that the pilot jets are equal sized (but really how likely would it be that they'd be different?)
Can you attach a clear tube to the bowl drain and open it to see how high the fuel level is (shape the tube like a J with the open end above the petcock). That'll tell you if the float is wacky. Generally speaking the fuel level should be +/- 1/8" from the gasket between bowl and carb body.

Could be a blocked passage in the carb too.

By removing the opposite plug wire,is that the correct procedure when adjusting the air-mixture? Just curious.

It gives you a better ability to tune one cylinder at a time for max performance. Get them both running at they're peak, and they'll work together at max performance.

I think my problem might have been that it was on its kickstand. The float was tilted and probably like you said flooding the pilot jet. I'm going to put it on my lift and see if that makes a difference. That will give me an idea on whether or not I need to pull the carbs, and adjust the float height.

Put a piece of 2 x 4 under the kickstand. That will level it out enough. Check the clamps on your rubber connectors to make sure it's not sucking extra air. Check your squirrel condoms too.