1985 XR 600 electrical issues

[Jrod]

So basically....

The other day my lights and horn stop working, got home and wiggle some wiring and it all came on and worked fine for about 2 minutes. Now I can't get them to work.

The bike still runs and measuing across the stator at idle its between 35-38v

Measuing across the regulator I get 0v? (well like 0.1 to be precise) I've studied the wiring diagram and the power from the stator goes directly to the CDI, this then feeds back to the Reg I guess? Is it likely to be a faulty CDI if no power is going to the reg or a wiring issue? As I say the bike still runs fine...
https://img176.imageshack.us/img176/5867/img0741l.jpg

Also I was considering it might just be a bad ground but where is the ground on this bike?!

[finpos]

You've probably just got a bad connection somewhere, the wiggled wire would be a good place to start. You'll really need to pull all the connections apart, clean them up and re-make them.

By the looks of things you have a very basic old-school electrical system:

You have two coils in your alternator, a full one less than normal.

One coil powers the CDI exclusively, which is why it runs ok without the secondary electrics.

The other coil powers the secondary electrics - directly with AC. "Regulator" in this context is probably a big fat wirewound resistor somewhere which does it's best to calm the worst of any excessive current produced at high revs. i.e. you do not have a traditional reg/rec on the bike!

As such, you should do any measurements on AC and expect them to vary a lot with revs.

My guess is that the bike does not have a battery at all?


f.

[Jrod]

No battery correct.

2 individual coils makes sense, I'll look into it more tomorrow...

[Jrod]

Sorted.

As soon as you said It had 2 coils I realised that just because the engine was running it didnt mean power was getting to the light system.

I traced the wire down to the stator and alas, it has shorted out on the frame.