No charging issue 900ss

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DaveG
Cucciolo - the Lil Pup
Posts: 16
Joined: Mon Aug 23, 2010 5:17 am

No charging issue 900ss

Post by DaveG » Wed Jul 08, 2015 7:08 am

Hi All,
After having charged the battery mulitple times I realised that the bike (900ss 1979) is not charging at all, the voltmeter doesn't move when I blip the throttle. The bike is fitted with an after market (5 wire) reg/rec, which I have tested the diode bridge and it checks out fine at that level.

The alternator, also checks out when measuring resistance to ground (of both yellow wires) i.e. infinite, and only 1 ohm resistance between the 2 yellow wires.

So digging deeper I checked the GEN lamp circuit which lights OK, and now I am staring at the stator/rotor! The magnets on the rotor seem fairly strong at least it grips my screwdrive fairly strongly, so my only conclusion would be to change the stator.... I have found the G92 stator on the Electrexworld site is that the best alternative, and do you agree with my troubleshooting so far?

Thanks,

DaveG

baddean
Parallel Twin
Posts: 144
Joined: Sun Jun 17, 2007 6:11 pm
Location: Cincinnati Ohio

Re: No charging issue 900ss

Post by baddean » Sun Jul 19, 2015 11:13 am

Dave,
Your trouble shooting process is good but maybe doesn't go far enough.
You say in your post that the "alternator checks out". You then go on to say that your "only conclusion is to change the stator".
The stator is the stationary part of your alternator. The two yellow wires come from the stator. It would appear that the stator checks good.
Even if the rotor magnets were very weak it would still produce some current albeit a weak one. Maybe the rotor will pick up the screw driver but will the screw driver pick up the weight of the rotor. The magnets will weaken over the years. As I said earlier though, even weak magnets will produce some current.
Make sure that you have a good ground for your after market regulator.
Are you sure that the battery itself is "good"? If you have had to repeatedly charge the battery maybe it is no longer capable of accepting a charge.
You haven't mentioned how old the battery is or whether it has been subjected to very hot or cold temperatures.
The volt meter shows voltage that is actually being imparted to the battery. If the battery is no longer capable of accepting a charge (shorted fused plates, low electrolyte, physical damage, sulfation) the volt meter will in turn not show a charge. Make sure that you have a good ground for the battery itself as well.
Hope some of this helps,
Let us know,
Dean
Faster, faster until the thrill of speed overcomes the fear of death.
Hunter S Thompson RIP

DaveG
Cucciolo - the Lil Pup
Posts: 16
Joined: Mon Aug 23, 2010 5:17 am

Re: No charging issue 900ss

Post by DaveG » Mon Jul 20, 2015 1:28 am

Hi Dean,
The battery is about a year old, and will hold a charge when I put it on the charger overnight, so I am assuming it's good enough. What leads me to believe the stator is bad is that I can not see any AC volts measuring across the 2 yellow wires, even though the resistance checks are good, as you say even if the magnets were weak, there would be something coming out of it.

I should receive an Electrexworld stator tomorrow or Wednesday, so will update you on what I find.

Thanks for your response.

DaveG

baddean
Parallel Twin
Posts: 144
Joined: Sun Jun 17, 2007 6:11 pm
Location: Cincinnati Ohio

Re: No charging issue 900ss

Post by baddean » Mon Jul 20, 2015 11:18 am

Hi Dave,
You hadn't mentioned the ac voltage check in your first post. No ac would indicate a bad stator.
Let us know how it goes.
Dean
Faster, faster until the thrill of speed overcomes the fear of death.
Hunter S Thompson RIP

DaveG
Cucciolo - the Lil Pup
Posts: 16
Joined: Mon Aug 23, 2010 5:17 am

Re: No charging issue 900ss

Post by DaveG » Wed Jul 29, 2015 10:24 am

Those barst*&*^ds on ebay showing 10 units in stock and then inform you (after taking your money) that they are waiting for delivery.

Should receive my G92 stator tomorrow....I will update once it's fitted.

DaveG

baddean
Parallel Twin
Posts: 144
Joined: Sun Jun 17, 2007 6:11 pm
Location: Cincinnati Ohio

Re: No charging issue 900ss

Post by baddean » Fri Jul 31, 2015 12:30 pm

Fortunately there aren't too many b...tards on fleabay, but they seem too poke their heads up out of their holes just when you need something they purportedly have.
Good luck and let us know how it goes.
Dean
Faster, faster until the thrill of speed overcomes the fear of death.
Hunter S Thompson RIP

DaveG
Cucciolo - the Lil Pup
Posts: 16
Joined: Mon Aug 23, 2010 5:17 am

Re: No charging issue 900ss

Post by DaveG » Thu Aug 13, 2015 1:05 am

A quick update. I eventually got my stator (G92) and they also sent me a rotor in the package, so I suppose I forgive them for the wait! :shock:

Fitted the stator and had to elongate the wires as they would not reach to under the seat, put it all back together and guess what.... it didn't charge!

But the symptoms had changed slightly, I was getting a constant (but small) AC current, and now the reg/rec unit was heating up significantly - just sitting there. I think if I had left it long, wires and insulation would have started to melt!

Anyway the only other thing in the circuit is the reg/rec, so I purchased a unit (RR51) which arrived in 2 days, and then fitted it and low and behold over 14 volts across the battery! I am not convinced that the stator was not also at fault as the symptoms changed, so I am pretty convinved that both units went out, although only really sure that the reg/rec was bad (even though all diodes seemed to function).

Anyway I now have a new charging system, and even the gen lamp is now working! And I have a free rotor as a paper weight on my desk!

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abmartin
SSD900 Darmah
Posts: 357
Joined: Tue Apr 10, 2007 4:08 pm
Location: New Brunswick, Canada

Re: No charging issue 900ss

Post by abmartin » Sat Aug 15, 2015 3:01 pm

From my experience the voltage regulator/rectifier fitted to bevel twins is troublesome so no surprise that this was the root of the problem. Thanks for the replacement reference.

Bruce
1979 900SS
Fredericton, NB
Canada

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