Hello I have a 1974 Honda CB 550, it's not charging. It has a new battery new wiring and continuity between wires. The field coil checks out at 4.9+ or -10%. The stater is brand-new rebuilt and it also checks out okay, yet I am still not charging what do I do now. I checked the AC votes on my voltmeter while running and I get nothing.
Need help on 1974 Honda CB 550
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Do you have one of these yet, and do you know how to read it ?:I
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Okay I tested the rectifier by the book check open in one direction and closed in the opposite direction not under a load but I have three rectifiers I also try and three regulators I'm not sure how to test the regulator. The stater is brand-new and never been used I detested for continuity between the three wives and also grounded each wire to the regulator itself for continuity. When I tested the generator I unplugged the stater from the wiring harness while it was running and tested the generator directly and received no power. this was at an idol Not 2100 RPM. Not running I get 12.5 on my voltmeter at the battery running it does not go up during acceleration. I do have a wiring diagram in the manual and one in color I seem to fall the wires pretty well throughout the motorcycle.
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"I detested for continuity between the three wives" 
that's priceless, spell check catches me up some times too.
that's priceless, spell check catches me up some times too.
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When you meter test the stator coils, you should be reading some resistance and not just continuity. It should have ~1 ohm of resistance I would think.
A factory service manual would give the correct test procedure and specs.
How did you manage to get a brand new unused stater assembly for such an old bike ?:I
A factory service manual would give the correct test procedure and specs.
How did you manage to get a brand new unused stater assembly for such an old bike ?:I
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Hmmm … as I see it (figuratively speaking)
It has what appears to be a single, 3 phase alternator, and not 2 separate coils for ignition and lighting.
The bike runs, yes? so I should think it must be making power or you are running dead loss on the battery.
You really should be reading in excess of 12 volts AC coming out of the first connector. If not, that would suggest a dead short between the power source and the first connector.
The regulator and rectifier come after that, so ….
Does the bike still run if you disconnect the battery ?
If no, it's looking like your stator has a bad ground, or a short in the wiring, or possibly is installed incorrectly and live shorting to ground.
Have you already tested for continuity between the connector terminals that are suppose to be live and the engine ground, which should Not have continuity?
It has what appears to be a single, 3 phase alternator, and not 2 separate coils for ignition and lighting.
The bike runs, yes? so I should think it must be making power or you are running dead loss on the battery.
You really should be reading in excess of 12 volts AC coming out of the first connector. If not, that would suggest a dead short between the power source and the first connector.
The regulator and rectifier come after that, so ….
Does the bike still run if you disconnect the battery ?
If no, it's looking like your stator has a bad ground, or a short in the wiring, or possibly is installed incorrectly and live shorting to ground.
Have you already tested for continuity between the connector terminals that are suppose to be live and the engine ground, which should Not have continuity?
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This flow chart is pretty much all you need - https://www.electrosport.com/media/pdf/fault-finding-diagram.pdf
No that being said my CB750 was not charging and I ended up being the connectors from the stator to the rectifier. Even if your stator is new, and you plug it into the factory wires under the side cover, it could have too much resistance and not be charging. When you tested the resistance of the stator winding did you test from big rectangular plug? or the bullet connectors under the cover?
Look at the diagram. I believe on these the regulator switches the power to the field coil on/off. You can jump a hot wire to the field coil from the battery + and see if that makes it charge. If so the regulator is at fault, or is not getting a good connection to the battery or field coil
No that being said my CB750 was not charging and I ended up being the connectors from the stator to the rectifier. Even if your stator is new, and you plug it into the factory wires under the side cover, it could have too much resistance and not be charging. When you tested the resistance of the stator winding did you test from big rectangular plug? or the bullet connectors under the cover?
Look at the diagram. I believe on these the regulator switches the power to the field coil on/off. You can jump a hot wire to the field coil from the battery + and see if that makes it charge. If so the regulator is at fault, or is not getting a good connection to the battery or field coil
Break even charging on a SOHC cb Honda (750, 550, 400, 350f) doesn't occur till between 2000 and 2200 rpm. If you are testing "charging" at idle you are wasting everyone's time including your own. You take a reading on your volt meter at the battery at 21-2300 rpm and then again at redline. That will tell you whether it's charging. By the way these charging systems suck eggs, if you see 13.7 volts at redline you are doing great, so don't expect 14v
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