SOMETIMES my carb will leak gas from the drain line when the bike is running and continue when I shut down the engine. After a while it stops and may not happen again for weeks or longer. Does this mean the float is sticking and would this cause the bike to run rich? Should I take apart the carb and try to fix this before attempting any carb adjustments such as pilot screw or jet needle? What should I look for if I take the carb apart?