Quote Originally Posted by DMAGOLDRDR View Post
An easy task to perform to flush the needle valves is,,,

Fire the engine and as it is running shut the petcock off. Keep the engine running until it starts to die from fuel starvation. Then open the petcock and sometimes the rush of fuel into the bowls will wash out fine debris around the needle valves and seats.

Sometimes it works and sometimes it doesn't but it is easy to do.

That is an excellent suggestion. My memory is not what it once was, but that reminds me: Alternatively, if you remove the air filter[s] and run the motor, you can rev it up a bit and quickly cup your hand over the air intake for each carb, one at a time. Listen for the motor to bog, and remove your hand. This will cause vacuum to rapidly suck most of the gas from the bowl and really swirling things around in there. All the fuel has to go rapidly through the valve, so it could knock the crud on through. Used to work with single barrel automotive carbs, too. Instant tuneup!

Note: If you leave the intake covered too long, you could also just flood that cylinder, so not too long. ALso, use a rag, not just your hand. That much fuel and you could backfire that cyl, which hurts like hell.