I know this topic has been beaten to death but I am having a hard time finding info on my specific problem.

I have done all of the tests that I've researched over the last week. I've checked/replaced the voltage regulator/rectifier, ohmed the stator(all read OL) and checked the stator voltages while running(4 pin connection).

The voltages are as follows. Bottom pin reads 15-16V, second up reads 27-28V, third up reads 4.6-4.8V and the top pin(isn't connected to anything) reads 18-20V.

The problem is the bike won't charge normally at idle, it slowly rises with rpm and the headlight dims when revving. I normally wouldn't post on a topic that has been thoroughly covered, but I am having a bit of trouble finding info on the 4 pin setup. it seems most people have converted it by now.

 

That is a single phase stator that puts out anemic power. Change to a three phase stator and voltage regulator and it will not run the battery down when idling. I went from the stock 17 amp single phase to a 34 amp three phase. Your voltage may be OK but what amps are they?

 

check your regulator/frame ground....i had to jump mine with a wire before it started charging correctly.

ymmv

 

While I agree with Running an external Ground Wire. I removed my 4-Pin system long ago. Kinda "saving" it tho, cause I like "stock" ****. [I believe that I have everything to make my FX completely Stock].
Much Less headache with the 2-Pin.

 

Thank you for the replies, I'm not sure what the amps were. I don't have a manual(Everything I have found has been off here) and I'm finding it hard to find schematics of the four wire system. Most of what I see is the two wire set up.

I'm going to the Davenport swap meet soon so I'll be sure to look for the upgrade system. Along with a few other parts.

 

You need the manual no matter what you decide to do. That should be your first purchase.

 

I know, that's usually the first thing I'd buy. I figured my father had one squirreled away somewhere but I haven't found one yet. It has been added to the list.

 

You really don't have to go to a larger system, you just need to sort yours out.

The older systems don't have much output at idle. As in nearly none. Once the revs come up you are good to go. I still run the two pin 17.6 amp setup in my 76 and it is only using half of the output running a 100 watt high beam at night. Why go bigger?

Griz