So I took my new to me 1991Ultra for it's first ride today. Not charging. Stator checks good, 33vAC.
Reg shows 12v from 1 pin to ground, other pin shows 2v - internet research diagnostic procedure tells me means bad reg/rect?
Looking and lightly probing at the stator plug it looks very much like the lower female contact within the rubber boot has been pushed inwards 1/8" or so. And very corroded. Has anyone experienced a stator contact loosened and pushed into the plug compromising contact?
Anything is possible I suppose....
Thanks for any comments.

 

Yes, to the stator plug issue. Common problem. Lots of info if you search "stator plug". That "bad" connection can cause the plug to overheat and melt. Primary oil also softens the plug over the years.

There are a few ways to fix this, with replacing the stator (with new plug) being one option. The other still requires you pulling the stator, but depending on your wrenching/skill level, you can replace the wires with a longer section of wire (10 gauge automotive grade) with the wires fed thru the old stator plug hole.

With the new wires option, the stator plug hole is filled with silicone, and the new connection is made on the outside of the bike using a weatherpak connector to the regulator. The only negative to this is, if you have to pull the stator, you have to dig out the silicone and wire.

If you replace the stator, and use the oem set up, your problem is solved for awhile. The rubber plug will soften from the primary oil, and eventually leak, my replacement stator plug lasted 2 seasons and then started leaking. I finally did the rewire and silicone solution. No leaks, problem solved. The only reason I replaced that stator in the first place was because of the same problem you had. I did not trust that weak connection and it was leaking oil.