GSX750S. Inspection. Charging system failure

Yay! It’s inspection time! I was delighted about the inspection.

I thought what a beautiful 750 bike this is, and as I talked with the owner, they mentioned the voltage has been acting suspicious lately.
I was hoping to wrap this up quickly, but these things do tend to pile up, don’t they? (ΦωΦ)

Looks like it might wrap up quickly? I had a good feeling about it… but it’s clearly burned out!
If it were just this, maybe we could pass inspection today? I was getting excited, but… of course the voltage didn’t go up…

Right?

I replaced everything. I soldered the connections with the hope that electricity would flow better through the crimped joints.

Now let me measure the AC generator directly. I think this is the quickest way to get to the bottom of it.

Yellow-White/Blue: Idle AC 4V, 3000 RPM 8V
White/Blue-White/Green: Idle AC 6.2V, 3000 RPM 11.5V
White/Green-Yellow: Idle AC 5.8V, 3000 RPM 11.3V

Hmm… those are pretty low readings. It’s probably the generator…

Next I’ll measure the fresh DC output from the regulator without going through the harness.

Idle 7V, 3000 RPM 14.33V—so it does go up when you rev it.
That’s a bit unsettling, I have to say.

I took everything apart to check for any other issues.

Currently, when I run the headlight through this bike’s harness, it’s extremely dim—there’s massive voltage drop.
Even at full effort, I can only get about 10,000 candlepower… this is something that really needs to be addressed.

Is there a replacement generator available? (ΦωΦ) Hmm…

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