Hi,

I have a 95 GS that slowly drains the battery.
I've followed a charging test guide ( http://www.bbburma.net/Documents/JohnBates_ChargingCircuitTests3.pdf) but I can't find anything wrong except that charging voltage is 12.2 volts @ 5000 rpm, and not the expect ~13 volt. I've checked and cleaned all connections. Didn't help.
In an act of desperation I bought and installed a new regulator but it's still not charging. 

Any advice?
What else could cause this?

Thanks in advance.

stator
rotor
or rectifier

It could very well be your stator. Follow the factory procedure for testing it. Also, don't replace parts at random hoping that it will fix your problem. Test, identify, fix.

Quote from: burning1 on June 01, 2010, 12:13:58 PM
It could very well be your stator. Follow the factory procedure for testing it. Also, don't replace parts at random hoping that it will fix your problem. Test, identify, fix.

I think he did follow a good procedure.

Quote from: bombjack on June 01, 2010, 11:55:03 AM
I've followed a charging test guide ( http://www.bbburma.net/Documents/JohnBates_ChargingCircuitTests3.pdf) but I can't find anything wrong except that charging voltage is 12.2 volts @ 5000 rpm, and not the expect ~13 volt.

If my charging voltage was 12.2, and all the other tests came out good, I would also replace the regulator.

Next, maybe there is too much load on the stator, because it is faulty, or too many lights, heated clothing, accessories, faulty wiring.

Thanks for your replies.  

QuoteIf my charging voltage was 12.2, and all the other tests came out good, I would also replace the regulator.

Isn't the rectifier and the regulator in the same 'module' ? I've replaced the rectifier (the one on the right hand side with big cooling fins on). I thought that the regulator was built into this as well?
If the regulator is a seperate module then where is it located?

I've tested the stator as described in the testing and it seems to be ok. I will retest this to night just to be 100% sure.

I've re-tested the stator and it's ok (according to the test). It outputs 50-75 volt AC on all three wires depending on rpms.
All test turns out ok, but the voltage across the battery terminals is 12.2 volt all the time.

Quote from: bombjack on June 01, 2010, 11:14:40 PM
Thanks for your replies.  

QuoteIf my charging voltage was 12.2, and all the other tests came out good, I would also replace the regulator.

Isn't the rectifier and the regulator in the same 'module' ? I've replaced the rectifier (the one on the right hand side with big cooling fins on).

You are correct.  My response about replacing the regulator/rectifier was directed more to Burning1...


So how old is the battery?  Maybe take that in to an autoparts store and have them test it.

Quote from: Paulcet on June 02, 2010, 09:48:25 AM
So how old is the battery?  Maybe take that in to an autoparts store and have them test it.

Battery is 3 months old. It'll hold a charge just fine if charge it manually.

I noticed something while testing today. When the RR is connected, the output from the stator is reduced to 1 or 2 volts AC on all three wires. When RR is disconnected, it's back at 50-75 volt AC. Is this normal?

I'm not sure what the voltage there should be with the RR connected, but 1 or 2 volts sounds too low. Are you sure its the correct RR? Is OEM?

Quote from: the mole on June 02, 2010, 10:47:56 AM
I'm not sure what the voltage there should be with the RR connected, but 1 or 2 volts sounds too low. Are you sure its the correct RR? Is OEM?

Yes, it's OEM.
I reinstalled the old RR but I'm getting the same readings with this.

Help! SOS ...please... GStwin fellow in trouble here... 
Anyone know the correct AC voltage at the three RR inputs pins? 75 volts or 2 volts?
Thanks in advance 

I connected a H4 bulb to the stator output and it lights up brightly when engine is turned on. So the stator output lots of power. With that out of the way, and the rectifier already replaced, what is left ?

Between the 3 wires of the stator there should be 75v or more at 5k rpm ,

most likely R/R is faulty,you can check it's diodes with multimeter as described in the link you posted.

I replaced mine, first with another old GS R/R that was DOA and then with GSXR R/R (which is great),

just because of this exact problem.

Quote from: bombjack on June 02, 2010, 10:36:21 AM
I noticed something while testing today. When the RR is connected, the output from the stator is reduced to 1 or 2 volts AC on all three wires. When RR is disconnected, it's back at 50-75 volt AC. Is this normal?

There should be some voltage drop but not as drastic , make sure there is continuity between all 3 stator wires

and no continuity between them and ground .

Also try running the R/R output wires directly to the battery ,see if it makes any difference

PS sorry for modifying my posts  but if it helps:
http://gstwins.com/gsboard/index.php?topic=51021

Problem solved! 
It was a bad connection in the fuse box/starter relay assembly , so the positive output from the rectifier was not connected back to the battery.
Thanks for your help!