OK i have a 78 puch/sears free spirit with a polini 64cc kit.
I was riding for a few hours yesturday. I was going above thirty when my moded suddenly lost power while accelerating. I pulled over and stopped. My engine was still idling. Then i twisted the throttle a little and dead. Its dead now.
I parked in the shade and sat down and smoked a few cigaretes.
Then I noticed my spark plug was bearly screwed in. I screwed it back in and still nothing.
When I flood the engine a bit it starts for a second then dies.
So I think/hope it may be a sparkplug problem.