The first tomos a35 I bought with the oil injection sucked. we got it running and rode it for a few but evidently the pump was bad and the engine seized. So needless to say I no longer use the oil injection and never plan on it because I can't afford to replace my engine parts as it is. BTW I do think it sounds like your engine may have soft seized but I don't know why the wheels locked. I had a minarelli once that the circlip came out of while running and tore the hell out of the cylinder and bike came to a screeching halt.