Sounds like your bouncy bobble kaboogle isn't working. Sorry I couldn't resist. Did you try taking the fuel line off at the carb just to see what kind of flow you get? You say its fine on the highway so I suspect it is probably ok but if you don't get a nice stream the screens on the petcock are likely plugged. I think there is also a screen under the needle and seat that could be plugged. Please let us know what you find.