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1976 Honda CB750K Charging Issues

devilindetail

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Hey everyone!

I'm new to the forum and have looked at about every post here trying to figure out how to get my bike going again. When I first picked up the bike it wasn't charging but a quick look at the rat nest under the cafe seat showed some wires undone from the r/r. soldered and connected them back up and like magic around 14 volts at 3K RPM. Was riding it to work one day and noticed the headlight get very dim so i parked it and saw that the green wire from r/r had ripped completely at the base. I was able with luck to get it soldered back on to the tiny piece of wire still remaining and get the bike home. I decided to get a new r/r so i wouldn't have this issue again and I ended up removing some wiring from the back rat nest, hooked up the new r/r but now it's not charging. A buddy of mine picked the bike up after hours of cursing and regretting ever removing any wires. He then, a week later tells me the stator is shot. I get the bike back, pull the stator do a quick test with a volt meter on ohm setting and it tests good according to numerous videos and posts on this forum. I then put it back in the bike but still nothing. I ran the bike, put it up to around 5k rpms and I'm still not getting any AC voltage from the three yellow wires. I then think okay stator is shot when it's running, buy new stator and field coil on ebay, pull old one and install new one still no AC voltage. Made sure volt meter was good by sticking leads in socket and get 120V. So anyone have any ideas of what it could be now? Maybe the Rotor? This is my first bike and I'd really like to get this figured out so I can enjoy it! Thanks!!
 
Test the rotor. Should be reading 4.5 OHMs (+/- 0.5 is safe). Multiple threads and videos on how to test the whole charging system. Just went through the same headache, I feel your pain.
 
I pulled the cover and tried testing the rotor but it's a permanent magnet type so it doesn't have the normal copper rings to test. I stuck the leads from the volt meter on there with my best guess and it read 4 ohms but I have no idea if it was just measuring the internal resistance of the meter or what. Super frustrating that it once worked no problem and now I can't figure it out. Nobody in Vegas wants to look at something that's almost 40 years old either.
 
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