Not charging, new Reg w/weird readings

[IXL2Relax]

Referencing the last two pictures. Does that show the ground wire you added at the regulator is connected to the Upper Motor Mount between the cylinders?

From Post# 16/17 -

Originally Posted by warlock69

Disconnected keyswitch to lights breaker connection and everything is peachy. 12.8V at idle to almost 15v revving it.

Maybe try this disconnect again - disconnect keyswitch from Lights Circuit Breaker. Then see if the voltage reading across the battery is better (nearer to normal) when running engine at High Idle (enrichener ON)...


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[decman]

Well I am an electrical engineer, well retired

You can NOT use an ohm meter on a live circuit, you will always get bad readings.
For bad connection testing on a live circuit you have to do a voltage drop test.

"
Disconnected keyswitch to lights breaker connection and everything is peachy. 12.8V at idle to almost 15v revving it."

Sounds like you have too much load or a mild short in your light circuit.

Originally Posted by warlock69

Stator isn't grounded, OL both AC outputs to ground.

Above I was trying to figure out a weird issue where with ignition on, grounds would show resistance. Verified today that when the key is off, regulator to ground shows 0Ω, with ignition on 24Ω. This anomalous and has to be related to the voltage issue. Couldn't tell you what is causing it though, I think it's haunted at this point.

If anyone knows an electrical engineer I'll buy him a case of beer if they can help. Thanks all for your help.

[brucstoudt]

Originally Posted by decman

You can NOT use an ohm meter on a live circuit, you will always get bad readings.

most VOM's i've used will let you know audibly or visually if you're on a live circuit while in the ohms range.

[warlock69]

Originally Posted by decman

Well I am an electrical engineer, well retired

"
Disconnected keyswitch to lights breaker connection and everything is peachy. 12.8V at idle to almost 15v revving it."

Sounds like you have too much load or a mild short in your light circuit.

This sounds promising to me. How does one go about finding a "mild short"? I'm more familiar with the kind that make smoke or cause non-op bulbs...

[warlock69]

Originally Posted by IXL2Relax

Referencing the last two pictures. Does that show the ground wire you added at the regulator is connected to the Upper Motor Mount between the cylinders?

CORRECT

Originally Posted by IXL2Relax

Maybe try this disconnect again - disconnect keyswitch from Lights Circuit Breaker. Then see if the voltage reading across the battery is better (nearer to normal) when running engine at High Idle (enrichener ON)...

Good idea, I'll do this again.

[decman]

One thing you have to remember that these older charging systems don't put out a lot. This is a 1990 4 speed, correct?
If you are get over 13v at cruising speeds I would call it good.
On my 1988 883D I never saw anything over 14v.
Remember those specs in the manual are for 3800rpm.

When I mentioned 'mild' short I was referring to when corrosion or dirt build up
around CBs and connectors that create a 'resistive' short between power and ground. Those circuit breakers can get pretty dirty/oily. Also check the connections in the headlight bucket.

If you are worried, install a voltmeter and then just ride.

[spoon]

Just my 2 cents, but I would not call those clean connections. Clean from oil and grease grunge, but not electrically clean. Bare metal free of corrosion is what I want. Any discoloration from shinny metal is corrosion. Lead on the battery terminals corrodes and should be cleaned to shinney metal. The insulator under the washer on the positive terminal is not ideal. After I have a good connection I coat the connections with an oxide resistant grease. Maybe the camera lighting is making things look not clean, don't know. Just the way I fly.