My GY6 Chinese scooter - a Pulse Big Boy scooter (150cc), all of the sudden won't take. If I try to start the scooter, it does crank, but won't start and then fuel comes out of the float bowl drain hose. So I took the carburator apart - it is clean, the floats are working and everything. I replaced the spark plug...still nothing. The battery is fine, as the lights still goes on with the first turn of the key. What else could be a problem...maybe electrical?? I really don't know much about scooters so any advice would be appreciated.