Voltages to check when diagnosing charging issue

unleashedlive

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I feel like I've read a lot of threads and learned a lot but I'm still not getting a charging voltage off the bike and my battery is dying on me.

'79
Checking resistance across the 3 white rectifier wires and I get consistent 1.4-ish ohms
Checking resistance between the brown and green wires from the stator and I get the right 4.5ish ohms
Battery voltage never changes from its starting 12.5ish volts (battery needs a charge, but regardless)
The manual I downloaded seems to talk about an adjustable voltage regulator but mines all sealed and I'm getting much different ohm readings like 440 and 1500 instead of 10.5 and 140 but idk if thats because the reg is different?

I'm wonder where else to look. I read one thread that mentioned the voltage off the brown wire should be about the battery voltage? Mine reads nothing off that.
 
Charge the battery prior to testing otherwise it'll sink the voltage that you're looking for.

You're revving the engine when testing? Should read 14-14.7V at 3000+ RPM, assuming your battery is charged.

The brown wire that goes into the alternator from the wiring harness should read pretty close to the battery voltage when ignition is on.

Your voltage regulator is non-adjustable and doing resistance tests on it won't tell you anything.
 
Yes I tried revving the engine and saw no voltage difference at the battery. It has charged overnight and I will attempt again today.
I got no voltage reading from the brown wire and a ground on the bike. If I'm not getting power from here in a resting ON state without the bike running, it sounds like the regulator would be the issue?
 
Ok went back and looked at more wiring diagrams. I noticed I had the brown wire from the reg leading right to the brown wire on the stator but some diagrams had it wired differently.

I put the brown stator wire to the bikes ground.
I put the brown reg wire up to the power.

I’m not seeing any increase in voltage.
 
Yeah, I had a quick second look at the wiring diagram and was going to triple check later.
Seems like you have the electronic regulator but the wiring diagram appears to have it wired like earlier years that had mechanical regulators.
 
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