i went to fly my 50cc bird today and the damn thing wont start. i took it home and started checking things out and found one of my a123 batts took a crap. so i hooked another battery up to my ignition and it still wont start. if i pull the plug and put it in the cap it has a good spark. engine is getting fuel. could my ignition have shorted out and ruined my battery? is it shorting to the engine when i put the plug and cap back on the engine? any help from you guys would be greatly appreciated.