81 CB650 Brat/Cafe Build

Well, she's road legal. Still buttoning things up though. Front wheel arrived with a practically new tire, still has the nubs. Threw that on, added some fork oil to get rid of some slop, and had to get a new battery. Old one was so dead it couldn't even keep the spark plugs going once started. Wrapped the grips in some old leather I had lying around, figured out the speedo, adjusted the rear brake and finally rode the hell out of it today. Still need to get a mirror though. And fabricate a better plate mount. And splice the control wires.

 
Right, so my charging system doesn't work and drains my battery. All the connections seem good. Guess I have to test the rectifier first. I really hope its not the rotor...
 
dmable44 said:
Right, so my charging system doesn't work and drains my battery. All the connections seem good. Guess I have to test the rectifier first. I really hope its not the rotor...
Click to expand...

Ohm out the yellows
 
Tune-A-Fish said:
Ohm out the yellows
Click to expand...

Today is simply not my day. I pulled the rotor cover off, and everything looks new. The insulation is good, no broken wires or anything and the contacts are clean. Dumb me for some reason started the bike. Well that plug thin below the rotor shot out and oil shot all over my foot and leg. Shit. So now I have no idea which way the plug goes in.

Anyway, Ill test the yellows on the rectifier.
 
What's left on the to do list - mufflers, fenders or twin disc on the front in the future works?
 
Not sure what else yet. I'm going to keep the single rotor for now. I'll change this as they come up or pop in my head.

As far as the yellows, the three coming out of the big plug on the rectifier correct? How do you ohm put 3 wires at once? Just checked the battery while running, it was 11.78 so it's obviously not the battery. The rotor and stater looked fine as well, so it has to be the rectifier or something stupid right?
 
I think it best ti introduce you to the DTT sparky: #cycleelectricalguru

http://www.dotheton.com/forum/index.php?topic=48646.0
 
So I checked the three yellows from the stater and they all read between 2-2.3 ohms with the multimeter set on the 200. When I ohmed out the rectifier side, I got nothing, no change. The meter measures 1 all the time and it just kept reading 1.
 
Check continuity in the rec if stock might be a good time to invest in a reg/rec from the guru he has em for fair prices to the ton
 
Tune-A-Fish said:
Check continuity in the rec if stock might be a good time to invest in a reg/rec from the guru he has em for fair prices to the ton
Click to expand...

Checked, had the red meter wire on the black rec prong and the black meter probe on each of the yellows. They all read in the 520s

Does the rectifier need to be grounded? More specifically, the factory rec mount (all metal) was bolted to the frame. Mine isn't anymore.
 
I can't remember and I just looked through all the tear down pics and couldn't tell. There is one other thing that has a rubber grommet, it still does. It's like two small metal boxes connected and mounted by the same bolt. The wires coming from those plugs are red sleeved. Not really sure what to call the part.

Edit: its the CDI ignition
 
So the rings on my rotor read 2.3, that tells me that the rotor is bad right? Shouldn't it be between 4-5?
 
That's a low # Be sure to clean the contact good to get the reading.

This: is a good tutorial for replacing it also, you may have seen it already.
https://www.youtube.com/watch?v=yVU_RUE0c4o
 
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