The International CBX Owners Association

I'd bet it is the rotor. Did you do the simple check of measuring the resistance between the slip rings? It has to be near 4 Ohm. Anything far less or more is bad. It's the most common failure on these next to brushes. I probably could have been more descriptive before, but this subject has been absolutely beaten to death here if you do a simple search.

Dave

Hi,

I know you have the UK bike, but can't remember now if it had it's original Euro alternator on it or the larger US version.

If the issue is with the rotor, I may have a spare Euro one.

Happy to come over to your place again to see if we can sort it out if that helps.

Paul.

Where, and when, are you reading 11.8v? Use a good meter to read at the battery, before and after starting the motor. Check again at higher rpm. Wait a few minutes and see if it doesn't rise in values, both at idle and again at higher rpm.

If you have access to an ammeter, see what the alternator is really putting out. I have a handy clip on ammeter made by K-D Tools. Pretty handy tool, and cheap.

Thanks again all - here's the latest.... everything all back together nicely, new parts everywhere etc. testing at the connection block behind the right hand side panel. Voltage does not vary regardless of engine speed, and is reliably 12 volts between either the black or white pins and earth. Resistance between any combination of the yellow pins is 50-90 Ohms at a range of engine speeds - could this indicate where the problem lies - I read somewhere this should be more like 5 Ohms - would this be a sign of breaking down coils etc? Or am i just hoping for a solution rather than diagnosing the issue. Happy just to get the alternator rebuilt but might be a waste of money if it's just old cabling at fault...

Thanks for the offer Paul - think this one's a Euro unit, might be worth a spin with a know good one if you have such an item.

Did you actually check the resistance between the slip rings on the rotor? I’m telling you, that’s the first thing you should check after the brushes. It will never charge with a bad rotor and you can do further damage by running it.

Daves79x

Thanks for that Dave, will check that this very afternoon. I saw somewhere else that replacing the battery for a larger one from the 1500 Wing can also help as the exciter field can take quite a bit of , err, exciting.

Cheers again, I shall prevail.

The Gold Wing size battery is a good choice, but has nothing to do with your charging situation. Find the charging problem and you'll be good. I'm betting on the rotor, as I think I've said three or four times here already. You do know that you have to take the alternator apart to check the rotor? If that manages to test good, then it's your regulator.

Dave

Thanks again Dave, I've taken the alternator off and apart again, tested the resistance between the slip rings and guess what....reading is only 1.1 Ohm. Having already replaced the regulator/rectifier unit, battery, brushes and cleaned up all connections, this is probably the culprit. Before taking the alternator off this time I checked the voltage at the battery with the motor running and it confirmed that effectively it just shows battery voltage and no more than that at any engine speed. (read on external voltmeter). Ie there is no charging voltage at all from the system currently. Guess I'm now looking for a new rotor as the last part of the jigsaw. Cheers.

Hi,

Which alternator do you have.

Euro Version: Or US version: Let me know which one and I'll see if I have a rotor.

Paul.

Not probably, it IS the problem. As I’ve told countless guys here countless times, it’s the most common failure after brushes. But everyone insists on doing it their way.

Dave

Really appreciate all the guidance, now hopeful to find a replacement or someone who can return this unit....

I should have listened to you earlier Dave, but that's my learning style. I at least now know how to strip, replace and diagnose most charging issues and the bike has an essentially new set of electrics. Smiles all round then. Hope we can speak soon Paul. Cheers for now

A little late but still relevant:

https://www.bbbikeshop.co.uk/cgi-bin/sh ... html#a1634

CBX1000 Rotor Rewind (Large)

Price: �145.00

CBX1000 Rotor Rewind (Small)

Price: �120.00

To Fit:- Honda CBX1000. (Twin Shock) 6 cylinder model. Rotor size: 83/46.5mm. Smaller type. Please note, this is a repair/rewind on your rotor, however, we do carry this item in stock, and is sometimes available for exchange. For details click on the image or "MORE" button.