Topic: Voltage drop through system, no charging output

[Davidov]

I needed a battery for my 78 CB750F. It sat for about 2 weeks during vacation/other priorities.
Starting was getting slow. Battery was about 2 years old, no problem really.

Replaced the battery with a standard lead-acid type.
After I started it and warmed it up I decided to install the Rick's Regulator/Rectifier unit that I bought a few months back.

Easy plug and play factory connector for the Rectifier.
White, Green, Black OEM type plugs for the Regulator. Straight forward.
Started up, revved to 3-4K RPM and found no charging voltage. 12.4DCV at best.
Idle was lower.

I followed the notes from Rick's, and tested power supply with Key ON at the Black "sensor" wire at the Regulator portion.
I was getting 11.4 volts at the Regulator. 12.4-12.5 directly at the battery posts.
A whole 1 Volt being lost through the system.
From my understanding, the alternator current can be lost to excess current draw and not charge the battery properly.

I inspected every connector. All were recently checked and treated with dielectric grease.
Frame ground and ground by coils both good.

Removed the headlight looking for chaffed or pinched wires. Nothing wrong here.
Found the voltage creeped back up to 12v when I unplugged the connector between the Main harness and the Right-hand Start/Stop switch.
I found the voltage would drop to 11.2 and then jump back to 12.1 or so just by changing the Engine Stop switch.

First big question, Is that normal?

I ran out of time. I know my next test should be resistance of the alternator assembly.
I got a little ahead of myself checking wires, but I figured I would find a loose ground, loose connector, pinched wire. etc..

Double checking with this guide
http://www.hondachopper.com/garage/troubleshooting_charging_system/troubleshooting_charging_system.pdf

Diagram
http://manuals.sohc4.net/cb750f/technical_reference/WD750F_78.jpg

[scottly]

I found the voltage would drop to 11.2 and then jump back to 12.1 or so just by changing the Engine Stop switch.

First big question, Is that normal?

When the stop switch is changed to run, it switches the ignition system on. One set of points will usually be closed, which will draw an additional 2.5 amps from the battery, lowering the battery voltage. 

[Davidov]

Need to mention, I have a Pamco ignition.

[colvinry]

I went through this same thing. Ended up ditching my aftermarket ignition key switch for some toggle switches. Right as rain. My bike came in a box of parts so I wasn't too worried about keeping the stock appearance. Verify the stator magnet and coil are working. Reference the FSM. You can verify the magnet is working by running the bike and placing a small screw on the cover to check the magnetic pull. Also verify the voltage running to the R/R from the switched 12v hookup. That's about all I can think of now.


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[Davidov]

Welp 
I should have trusted my experience and knowledge to chase down this problem instead of reading too hard into the instructions that came with the Rick's unit.

No charging output would mean....something wrong with the alternator.
After I inspected and measured all the wiring, I found one connector of the Stator has no continuity.
I thought maybe a wire was pinched in the shifter cover, but all looked out. Some of the windings must have an open.

I would still like to compare though, can anyone give me a reference?
Measure Voltage at the Pos and Neg battery terminals and then measure Voltage at the regulator black wire?

Any recommendations where to buy a Stator? 4 into 1 doesn't seem to have them, I saw some NOS parts on ebay.