Hi all I’m working on an ’83 XT550. The carb is leaking fuel. Some facts: 1. The floats are fine, they are not leaking. They float if put in gas. 2. The float height is according to spec. 3. The carb needle looks perfect. 4. The valve seat looks perfect. 5. The valve is 100% tight if I tilt the carb to let gravity help the float push on the needle. However if I put the carb in the bike (or hold it vertical) one of the following happens: 1. The carb does not leak fuel 2. Some fuel drips from the overflow. 3. Fuel gushes from the overflow AND the breather tube, meaning the carb us FULL of fuel 4. If I tap the carb with a screwdriver the carb stops leaking fuel.. SO – the valve or float somehow get stuck and let fuel by, until I tap the carb, then the needle valve closes and the leakage stops. I have had the carb apart maybe 20 times, but can’t spot how the needle or floats get stuck. Everything moves smoothly and there is no snagging. Any ideas???