Generator light flickering at higher revs

[Rossheff]

Hi, I'm new to this board so apologies if this has been answered elsewhere. But I have tried to find it with no luck.
So the gernerator light on my 1968 912 goes out as it should on start up.
It then glows dimmly at at idle when I put lights on.
It then flickers and glows bright at higher revs.

I've taken readings at the generator and it kicks out a fairly steady 12-14v at idle, but then drops right off when I rev the engine. It will fluctuate between about 10v down to 0v with no real pattern.

I just fitted a brand new generator and the issue is exactly the same as with the old one...

Any suggestions gratefully received!

[WFBowen]

Check all of your wiring, especially your grounds. I’m no electrical expert, but i’d replace your voltage regulator.
Good luck
Bill