Page 1 of 1
Alternator issues....by the book ?
Posted: Tue Dec 08, 2015 6:50 pm
by cbxtreeme
This is in reference to this topic
viewtopic.php?f=102&t=10008
I know this is NOT a new topic, but I went through about 5 pages of questions, and found most of my answers.
But not all my answers.... So......
My 1979 CBX was not charging...so I pulled the alternator apart to find out why.
Bike has carbs off at the moment so I have to do testing by the book, each part of the charging system at a time.
IMG_6929.JPG
I dug around for the left over parts I had when I put my CBX together the first time, around 20 plus years ago....and found a spare alternator.
Just in case I might need something from it.
IMG_7003.JPG
Problem with the spare is obvious....someone did not want the clutch to slip.....
IMG_6965.JPG
First thing I tested today was the rotor...
The one on the bike had a reading of .9 between the two coppers rings where the brushes make contact.
Not good from what I have read,
So I tested the other rotor I had and it read 3.8 across the two copper rings...
From what I have read here it's supposed to be 4...
First question....would 3.8 be OK?
If so, my project tomorrow is getting that clutch off...unless the consensus is the welded AND screwed together clutches would be better like this?
Something tells me not....

Re: Alternator issues....by the book ?
Posted: Tue Dec 08, 2015 7:22 pm
by cbxtreeme
The next test I did was for the stator.
The spare stator I had, was missing the plug.....so no real spare.
My book showed how to do the testing, which is pretty basic.
IMG_6869.JPG
The issue with my testing was I could not get a constant reading through either of the testers I had.
And when I tested the first time, the readings were lower than when I got the garage temp up to 65.
After the garage was warm, I had a reasonably level reading of between .2 to .4.....but it still went from 0.0 up to 1.8...
I don't know if this is an issue or not, as I couldn't find anything similar anywhere else here or in the book.
I noticed that one of the brushes was also just about worn to nothing....so I definitely need to get those either way....
Continuity to ground....?
What part of the stator is considered ground?...the outside ring?
Re: Alternator issues....by the book ?
Posted: Tue Dec 08, 2015 9:32 pm
by daves79x
Your rotor is bad at .9 OHM. The other one is OK at 3.8. You'll obviously have to cut the clutch apart with a torch. Your stator is fine, I'm sure - I've never found a bad one, but tons of bad rotors, but I'm also sure you've already read that. If your brush is worn to or beyond the scribe line, then it's shot. Change rotors and brushes and bearings and seals and you'll likely be good to go.
Dave
Re: Alternator issues....by the book ?
Posted: Tue Dec 08, 2015 9:34 pm
by cbxtreeme
My regulator is a newer design, that I put in the bike many years ago.
I used the book to get me the numbers I needed, to see if my regulator registered to the same specs...
IMG_6867.JPG
When I did the testing, my numbers came out about the same.
But seemed to change depending on which end of the circuit I put the red tester end on, and the black tester end on...?
Re: Alternator issues....by the book ?
Posted: Tue Dec 08, 2015 9:46 pm
by cbxtreeme
daves79x wrote:Your rotor is bad at .9 OHM. The other one is OK at 3.8. You'll obviously have to cut the clutch apart with a torch. Your stator is fine, I'm sure - I've never found a bad one, but tons of bad rotors, but I'm also sure you've already read that. If your brush is worn to or beyond the scribe line, then it's shot. Change rotors and brushes and bearings and seals and you'll likely be good to go.
Dave
I guess it's a good thing I never throw anything away...
I'll get the clutch off tomorrow....grind and drill, don't want to get too much heat into it with a torch. (although I guess it's already had heat into it from welding it up everywhere, which is probably why the oil seal looks shot in it)
the other housing has a newer bearing and seal in it, but I'll check on those parts too if still available...for a fresher start.
Thanks for giving me hope that I can fix it easy....

Re: Alternator issues....by the book ?
Posted: Tue Dec 08, 2015 9:57 pm
by Rick Pope
Bearings are common, 6201 and 6203, Seal is also common, but I can't remember the measurements. Any good auto parts store should have it all, but the Honda parts numbers won't be of much use there. Auto parts store should fix you up for less than $30. Genuine Honda will likely be $60 or more.
When that clutch was welded, it likely took out the seal, allowing oil to the normally dry rotor/stator. Oil and brush dust makes a conductor which will fry everything. Don't ask how I know...................
Re: Alternator issues....by the book ?
Posted: Tue Dec 08, 2015 10:01 pm
by cbxtreeme
Luckily it didn't fry the rotor in this case...
At least not yet..............

Re: Alternator issues....by the book ?
Posted: Wed Dec 09, 2015 5:41 pm
by cbxtreeme
Ok.....
I got the clutch off the spare rotor, after a bit of work.
But then found the nut on the rotor shaft pretty trashed.
IMG_7006.JPG
Once I got all that apart, I see there is no oil seal as well......some people shouldn't be allowed to use tools....
IMG_7008.JPG
One question that I haven't found an answer to what is considered the ground on the stator. If it is the outer ring, and I put one test end on that and the other test end to a yellow wire....should I get a reading of continuity like this? Or is this not the ground that the book talks about?
IMG_7010.JPG
Re: Alternator issues....by the book ?
Posted: Wed Dec 09, 2015 11:44 pm
by cbxtreeme
Another possible issue with the charging system work load...
I have an ignition kill for drag racing wired into the ignition switch, and a ignition kill wired into the coils for the airshifter kill switch.
Would this cause the alternator to overwork and burn up at some point?
Re: Alternator issues....by the book ?
Posted: Tue Jan 05, 2016 9:03 pm
by cbxtreeme
Stator was bad....clutch spring shot....nut to hold clutch to rotor shaft history....
I decided to bypass the whole system, and get a conversion setup using the Kawasaki alternator.
And now I have a working charging system.
Re: Alternator issues....by the book ?
Posted: Wed Jan 06, 2016 10:27 am
by Larry Zimmer
Given that 'authenticity' is not an issue, I'd say that was a good move at this point, extreeme. Happy trails,