Electrical experts - 110 engine in 125m chassis

[Baba Yaga]

Hi all! Picked up a couple cheap trikes. One wasn't running, but now is after a fuel system go-through.

It's a 1985 ATC125m chassis, with a CDI 110 engine installed. I believe all the 125m harness is in place.

Headlight and taillight are not hooked up/working. In my service manual, I see that the 110 has one yellow wire, and one brown/black wire coming out of the alternator. The 125m diagram shows 2 yellow wires, and one brown/black wire coming out of the alternator.

The 125 harness has a double connector on the trike. The single yellow wire from the alternator tests around 18 volts AC when running. This wire is not currently hooked up to anything.

What would be the correct way to wire this up, and get the lights working?

It appears the 110 trikes have no RR. If so, I'm guessing a 110 simply regulates by load, which also would mean the lights would get somewhat brighter with increased engine rpm.

Since the 110 diagram shows the yellow alternator output going to the light switch circuit, perhaps this is what I need to do with a jumper wire. And since this trike now has no starter or battery, can I simply not use the regulator & circuits?

Anything else that would need to be bypassed, omitted, etc.? (I would like to leave the chassis & harness as stock as possible, for future 125m engine fitment).

Thanks!!

[Baba Yaga]

So, I ran a wire from the alternator yellow output terminal, up to the brown/black wire that goes to the headlight switch (behind the headlight), and voila. We have lights.

No smoke or fires yet.