Moped Army

I took a look at some pictures of the Grand Prix and I can tell you that it does not have the typical Laura M48 engine that is on most Batavus, like the VA or Starflites, nor is it he M56 like on the Regency, so any specs or diagrams you used referring to them may not be right for your engine.

I can tell you how wiring USUALLY works, though. There are usually three wires attached to the coil (not counting the spark plug wire). One is typically easy to see running from one coil terminal to ground, probably black. It often is grounded to the coil frame itself. There is usually a colored wire coming out of the flywheel delivering voltage to the coil. There is probably another wire, maybe black, sharing a terminal with that wire. This is the wire for the kill switch, which basically grounds the voltage so it doesn't flow through the coil. You can't really refer to the terminals as positive and negative, since the magneto puts out AC, which you need to remember when using a meter to measure voltage.

Good luck with your bike. $10 still sounds like a great deal. Pics?