charging system issue

Did you test the voltage regulator


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If there was a short, it would pop a fuse or circuit breaker.

Look at your grounds first. Make sure all of them are clean and NOT on painted parts.

Yes new voltage regulator, checking all for ground, funny thing if I un plug my headlight charging system shows 13.08 and climbs. All looks good at headlight but both the yellow and white wires when ohm tested show a ground with battery disconnected. I would hate to take to dealer. Any thing else I can try?

Have you measured the voltage, at the output leads of the regulator? That would eliminate the wiring from the regulator to the battery. If you have the proper voltage at the regulator, then trace the circuit from there to the battery. If you don't have the proper voltage at the regulator, then either it's bad, if your measurments at the stator are correct.

What are you using to tell that the battery is fully charged? Green light on the tender? Just curious because it could be a bad battery. If the battery is bad it will act like a load and the 13+ volts from the regulator might not show because of the load created by a bad battery. Disconnect the battery negative with the bike running off the power from the VR and see it it climbs with RPMs.

Also, just noticed "headlight charging system". What is that exactly?

Check the headlight relay.
From memory, the headlight gets power from the blue wire in the hi/lo switch. The blue wire powers the white or yellow wire depending on the switch position.

SCHMIDTYS said:

Check the headlight relay.
From memory, the headlight gets power from the blue wire in the hi/lo switch. The blue wire powers the white or yellow wire depending on the switch position.

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No headlight relay on that bike, but as you said, the blue wire from the "Lights" fuse powers the dimmer switch in the handlebar control.

As far as checking the stator output, I have had them read correct voltage, but the charging system was still not working, even with a new regulator. New stator cured the problem.

The stator could be malfunctioning only under load.

Thanks everyone here's the skinny: new battery, new voltage regulator, new 30 amp breaker fuse, stator reads 40+ AC, when I remove head light bulb using a volt meter on DC battery reads 13+ volts. when bike is throttled up I will get 13.8+, Put bulb back in (new dealer bulb) and battery reads with bike running 12.5 if brakes applied or passing lights turn on battery continues to drop to 12.3, at this point shouldn't the battery read in the 13's like it did with bulb removed and wouldn't this tell me something is grounding in the lighting circuit. Head light is composed of double white lead to 1 bulb terminal a white lead to the other and a black lead to the last. With battery disconnected all white leads show connectivity to ground. Thanks again everyone please keep suggestions coming

Your headlight wires read to ground, most likely because of other lights on the same circuit. Are the stator readings with the regulator hooked up? If unhooked, test with it hooked up and see what the difference is. Still haven't heard if you tested the voltage at the regulator output.( will need to probe wires) But that would tell you if the problem is up stream or downstream.

Remove the clutch lever perch and inspect the wire harness for pinched wires. The headlight wires feed thru the dimmer switch.

jsf103234 said:

All looks good at headlight but both the yellow and white wires when ohm tested show a ground with battery disconnected.

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What do you mean "show a ground"?

Exactly what did you do here, what were the ohmmeter probes touching?

jsf103234 said:

Put bulb back in (new dealer bulb) and battery reads with bike running 12.5 if brakes applied or passing lights turn on battery continues to drop to 12.3, at this point shouldn't the battery read in the 13's like it did with bulb removed and wouldn't this tell me something is grounding in the lighting circuit.

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If the system is working properly it should read the same with the headlight on or off.

But something is wrong here, and I am suspecting the stator is not working under load, or a poor connection somewhere between the voltage regulator and the battery.

Both positive and negative cables must be making a good electrical connection, and the regulator must be making a good connection to the frame ground.

There is nothing grounding in the lighting circuit, if that were the case it would simply blow the fuse.

Test the the stator AC output volts again, should be approx. 15v AC per 1000rpm. It should measure over 60v AC when the engine is revved. 40v AC is low. The rotor splines might be stripped causing it to coast on the crankshaft, equals low volts.
DC volts at the battery should measure around 13.5v with engine running and lights on.

FYI,
This turn out to be the stator. when circuit complete via plugging in front light it was too much for the stator. This is why i got conflicting results. when tested stator was showing a ground and was burnt.
Thanks everyone!

Thanks for the update.