Our problem is that when you mash the gas it takes lots of tries for it to start "rumbling" and go. You have to mash the gas pedal down about an inch only for it to start. Then, once the motor starts up you keep mashing the peddal and it goes. If you mash the peddle to the floor initally it will not go. It is not the battery - that is fine. And, once you ride for a bit then it starts better but you still have to start it slowly. I am not sure this is related but it has begun to back fire. Please help. My husband is a procrastinator and I am a teacher who needs to ride this summer. 