Ok, I still don't know for sure, but I think it's a problem with a sensor inside the engine.
When you take off the chain guard part of the case I find one connector with 6 wires that goes to a little black thing bolted to the motor. This black circle has an "L" shaped knob that sticks inside the motor and into a bolt with a groove in it. This connection must be for lights that I don't have, because the connector is just tied up but not hooked to anything. When I take it apart, and hook the meter up to it and spin the thing by hand, it produces power based on how fast I spin it. By hand the most I got was 0.4 volts.
That seems like at engine speed it would produce lots of power, but again, it has no connection ,so it isn't doing anything.
Next are 6 more wires that go through a rubber grommet into the engine case. Kicking the engine over, no combination of wires produces more than 0.1 volts, so I think maybe these are the problem. Now the question is WTF is the first sensor that isn't hooked up, and 2nd what do those wires that go through the grommet into the case hook up to?
I know I rambled, sorry
I appreciate any help at all, the little guy is upset about not being able to ride.