Yes, the float needle may be sticking. If you remove the carb and unscrew the bottom float bowl. The whole thing just unscrews. Careful of the gas in there.
Once in you will see your float bobber. That is held on by a pin. Push that pin out and you will be able to remove the float. You will see in a little channel on the float the needle valve. Check that the rubber tip is not too misshapen. If it is then you will want to replace it. If it looks ok still, no bloating or smashed tip, then you can give the needle tube a nice clean and polish, which should help it from sticking. If it still persists then the needle may need to be replaced.
treatland will have all the goodies you need to rebuild the carb.