What you describe sounds pretty close to what I think I'm seeing. I get enough fuel to the carbs when I'm trying to start cold, with choke, and then it's like the flow just stops when the bike warms up. I've looked at the needeles but I'll check them again to make sure I didn't miss something.
Point of clarification - When I mentioned 'needles', I meant the float valve which is part of the float (one per carb). Because it sits on the float it goes up and down with it opening and closing flow to the bowl.
Try this - remove the bowl and the fuel inlet line to the carb. Attach a tube to the carb fuel inlet. Blow in the tube and move the float up and down. With the float down, air should flow, with it up, air will stop. Same with fuel. This will verify that your float circuit is working well. It might even free up a stuck float valve.
