GS1100EX Regulator/Rectifier

[Nessism]

Hello again

I know we are in August, probably most people are on vacation and with the heat it is, the last thing people wants is to respond to a newbie. I'm looking for in other threads about how many volts has to indicate the voltimeter with lights on.
I've been reading this thread: https://www.thegsresources.com/_foru...ICK-TEST/page9

But not say nothing about lights on. That's why I'm asking if it's normal 12,5V with lights on, in any rpm. (from 1500rpm till 5000 rpm).

I need to close this electrical problem, because I have other problem with carburators and I will open other thread in its corresponding section

Sorry for insisting

Regards

12.5 VDC is not good. Even with the headlamp on the system should put out at least 14 VDC at 5000 rpm. Further, there should not be 15 VDC at any time, lights on or otherwise. Did you wire the system properly per the diagram I posted earlier? Bypass the factory wiring?

[Sparkie]

Hello Nessim,

I think yes. The 3 wires without polarity goes directed to the stator wires. The black one goes directed to the negative terminal in battery. The only wire that I have connected in the same place that the older rectifier it's the brown ( positive in sh775AA). I have connected this in the same wire where it was connected the original rectifier (the red one)

Later I will post some pictures.

Regards

[Sparkie]

I just open the front light / Headlight, and the bulb it's 12v100/90W ... instead 12v55/60W
Could this be the reason so the motorcycle don't charge more than 12'5v when the front light it's On?

[Brendan W]

I just open the front light / Headlight, and the bulb it's 12v100/90W ... instead 12v55/60W
Could this be the reason so the motorcycle don't charge more than 12'5v when the front light it's On?

It could account for the 12.5 at idle but not at 5000.
You may have bad contacts at other points in the system. The fusebox, the headlight connector plug, handlebar switches etc.
IMHO that bulb is too big and is likely to develop quite a lot of unwanted heat in there.... if it hasn't already.

[Sparkie]

Hello again, I'm sorry for disappearing so long, but I could not continue checking my electric problem because I had a serious problem with carburetor. I had to buy a second hand carburetor and rebuild it. Thank you very much for the fantastic Ed Ness tutorial: https://thexscafedotcom.files.wordpr...d_tutorial.pdf

Now in my short free time I keep trying to solve this electric problem.

Like Nessim tell me, I bought one SH775 R/R and it's installed, but the result it's the same. The Bike charge the battery with lights off. But with lights on, or even I tried with frontal light off and with the rear brake light on, the regulator neither go more than 12.5V in any rpm. Only charge with all lights off.

This morning I begin to check de stator.

According to Clymer Suzuki book gs1100 fours, for check the good shape of the stator I have to connect an AC voltemeter between the three stator leads.

White/Blue and Yellow
White/Blue and White/Green
White/Green and Yellow

The result have to be 80 volts AC or more at 5000 rpm in each connection. Well... this it's my result:

With the motorbike just started I get just 80 volts AC in two of the connections and in other near 80 (between 75-79)
But when the bike begin to warm (about 10 minutes with the motor running), any of the three connections arrive more than 74-75 volts AC at 5000 rpm.

Could be the stator my problem with the system charge?
Could be that the stator doesn't has the enought strong for charge the battery when begin to warm and the lights are on?
My bike's stator it's the original one, it have near 40 years......

Sorry for this brick text

I wait your answers, and of course, Merry Christmas and a Happy new year.

Regards,
Juanmi

[bonanzadave]

Later I will post some pictures.

Regards

Please do. Just to make sure hookup is correct. Grounds are important. Is the SH775AA mounted to a plastic fender ? Fuses are all good ? Batt good ?

I think your stator output is fine. Its the SH775AA or your wiring. Im OK when my bike voltmeter shows 13.8 - 14.3vdc and it normally does at or above 2-3k rpm.

[posplayr]

I did a quick scan and I don’t see anywhere where the op tested the stator. Leg-leg and leg-gnd at 5k rpm. Weak stator would explain why charging cannot reach full voltage under full load.

[bonanzadave]

op tested the stator.

With the motorbike just started I get just 80 volts AC in two of the connections and in other near 80 (between 75-79)

[posplayr]

With the motorbike just started I get just 80 volts AC in two of the connections and in other near 80 (between 75-79)

By far the most productive test is leg ground not leg leg.

[Sparkie]

Thank you bonanzadave and posplayr for your quicks answers. The SH775A it's mounted in the bike provisionally not the definitive, is mounted only for testing, not for riding (it's hanging on a flange). All the fuses are news, the battery it's new too. The general wiring in the bike.... uffff... I donīt like it very much :/ .... Could be a bad lead or connection, but Which?... I wouldn't know where to start.

Tomorrow I will take some pictures so you can see it better.

[posplayr]

Thank you bonanzadave and posplayr for your quicks answers. The SH775A it's mounted in the bike provisionally not the definitive, is mounted only for testing, not for riding (it's hanging on a flange). All the fuses are news, the battery it's new too. The general wiring in the bike.... uffff... I donīt like it very much :/ .... Could be a bad lead or connection, but Which?... I wouldn't know where to start.

Tomorrow I will take some pictures so you can see it better.

Normally you could report the 6 voltages of the Quick test results and we can help you diagnose the charging system. However in this case I would suspect the stator and as yet you don't seem to have tested it exhaustively.

The Phase B tests involve the stator separately from the rest of teh charging system. The leg to ground is the most useful. You can ignore the ohm meter test they are included for historical completeness despite being an irrelevant distraction.

https://www.thegsresources.com/statorpapers4.php

[Sparkie]

Normally you could report the 6 voltages of the Quick test results and we can help you diagnose the charging system. However in this case I would suspect the stator and as yet you don't seem to have tested it exhaustively.

The 6 voltages of Quick test are perfect in my bike with lights off. Perfect, perfect, perfect. But when I swich on the light (front head) or I keep footle/step the rear break pedal, the 6 voltages donīt go more than 12 - 12.5 in any rpm.

[posplayr]

The 6 voltages of Quick test are perfect in my bike with lights off. Perfect, perfect, perfect. But when I swich on the light (front head) or I keep footle/step the rear break pedal, the 6 voltages donīt go more than 12 - 12.5 in any rpm.

I have no idea what perfect means as it is the interrelationship of these voltages that provide the clues to diagnose the problems with your bike. Do you still have low voltages with headlights on? Is you them how can you possibly have perfect voltages?

[Sparkie]

With "perfect" I want to say that the bike in each one of the 6 steps the voltages are correct according to the test values. But ALWAYS with all the LIGHTS OFF.

In the moment I SWITCH ON some light (Front Head, Rear Brake), the voltage in steps 3, 4 and 5 (1500 rpm, 2500 rpm and 5000 rpm) donīt exceed 12 - 12.5 v

I'm sorry for my English ^^!

[posplayr]

With "perfect" I want to say that the bike in each one of the 6 steps the voltages are correct according to the test values. But ALWAYS with all the LIGHTS OFF.

In the moment I SWITCH ON some light (Front Head, Rear Brake), the voltage in steps 3, 4 and 5 (1500 rpm, 2500 rpm and 5000 rpm) donīt exceed 12 - 12.5 v

I'm sorry for my English ^^!

Other than Steps 1 and 6 (Key Off) all the Quick test steps are with the lights ON !

In the US we have mandatory lights on while so all bikes (since about 1982) are wired lights on with key on.

In the moment I SWITCH ON some light (Front Head, Rear Brake), the voltage in steps 3, 4 and 5 (1500 rpm, 2500 rpm and 5000 rpm) donīt exceed 12 - 12.5 v

I'm sorry for my English ^^!

You probably do not have enough power coming from your stator and so the charging system can not deliver power/voltage under standard loads.

You can neither just replace the stator or try to get some confirmation first from the leg to ground tests. They shoudl report ZERO VAC.
You will also probably find a burned stator.