All stators make AC. Believe it or not, there's no such thing as a DC motor, or DC generator. There's only AC, the DC comes from a mechanical commutator. Anyway, the stator sends it's power to the voltage regulator. The ZX voltage regulator appears to have a full wave rectifier in it. Think of a sine wave, will all the humps moved on top, none on the bottom. Then the voltage regulator part, cuts the tops of the humps off, until it looks like all humps on top, with the top of the hump being flat. Around 14 volts
The thing is, the voltage regulator isn't a actual zener. It's some power FETs (transistors) that switch on and off to limit the maximum voltage. (poor mans zener). Anyway, we took one apart, but haven't made a schematic yet. But, just looking at it, looks like about 10 dollars worth of parts in the case.
If you put it on a scope, it will look crazy, that's because of the poor man's zener, instead of a real zener. So, it's a crazy DC, that's moving all over the place. That's why your meter trips out. It won't power any electronics, safely, without some more electronics behind it. But, headlights and handwarmers don't care what the power looks like, they just want power.