I had a Super Tigre G51 on a U-CAN-DO .46 that did the same thing and I had a Great Planes Easy Fueler Valve on mine. What I did was lean out the low end until I had a nice idle. When I was not flying, I keep the fuel line hooked up to the fuel value so the fuel wouldn't siphon back into the carb. Just start leaning out the low end until you get a good idle and don't remove the fuel line out of the fueler until you have refueled and ready to start the engine.