Alternator issue?

[ricksgs750es]

I was riding along on my '83 GS750ES and noticed the lights very dim. Then, the engine completely turned off on me. I would let it sit for a few minutes... Start the engine again and it ran for a few minutes... Then it wouldn't start at all. I had installed a new battery several days before...

Think it's the alternator? I saw one on eBay and thinking of buying it if you think it's the case... Maybe the rectifier?

[BassCliff]

Stator papers

Hi Mr. ricksgs750es,

Have you gone through the Stator Papers or the charging system troubleshooting chart? It's hard to say exactly until you've done all the tests. What is the voltage across the battery terminals at idle? At 4000 rpm?

Start by cleaning ALL of your electrical connections on the wiring harness from the head light bucket to the tail light, fuse box, and all the ground connections too. Run the ground wire from your regulator/rectifier directly to the negative terminal of your battery. Then retest.

When my bike quit charging, I bit the bullet and replaced the r/r (Thanks Mr. duaneage!), the stator and installed a new AGM battery. I'm hoping the battery will last 5 or 6 years but the rest should last another 20.

Thank you for your indulgence,

BassCliff

[ricksgs750es]

thanks for the info. I'll check this stuff out.

Hopefully, I'm going to start restoring it soon and will take it completely apart from head to toe. So I was debating whether I should go this
process. I was thinking of replacing the stator and rectifier anyway..

I'll check the info first.. It's going to be a few months before restoration anyway.

[posplayr]

It is worth attempting to fix without replacement

There are a high percentage of occasions where getting the R/R + and - terminals to be close to the battery + and - terminals respectively at 5000 RPM as well as idle will restore proper charging.

Even if you would feel better with new parts, it is best to solve the grounding and connections problems first as you may have simply put new parts into a situation where they will suffer the same destructive fate that the old ones would have without fixing the connections.

I took an over charging bike and got it to charge fine by doing this Only then did I swap out the stator to electrosport but still have the electrosport R/R in the box.

Posplayr

[BassCliff]

Hi Mr. ricksgs750es,

I forgot to mention that the tests proved my stator was actually the cluprit. But the battery was old and barely holding a charge and I wanted to change out the puny little stock r/r with a Honda upgrade part from Mr. duaneage. You can read about my stator replacement on my little BikeCliff website. And if I haven't given you your own mega-welcome, please feel free to pick one up HERE. The mega-welcome page has lots of information to save you lots of searching. Keep us informed.

Thank you for your indulgence,

BassCliff

[Eli69]

The Stator Papers - five stars *****, two thumbs up, a must read, a real page turner! Better than fried chicken, more american than apple pie! freshens your breath and gets rid of acne! i was a 12.54 volt weakling constantly riding in semi darkness, now i'm up to 14.5 volts thanks to the Stator Papers!

[lurch12_2000]

I was riding along on my '83 GS750ES and noticed the lights very dim. Then, the engine completely turned off on me. I would let it sit for a few minutes... Start the engine again and it ran for a few minutes... Then it wouldn't start at all. I had installed a new battery several days before...

Think it's the alternator? I saw one on eBay and thinking of buying it if you think it's the case... Maybe the rectifier?

If the battery is new then I would use a charger on it so when you figure out what the problem is, you're not spending $40-80 for another battery.

When I replaced my faulty stator, I used the stator papers mentioned here to pinpoint the problems(r/r was bad too). I considered a used stator for 1/2 price on e-bay but figured it was worth $100 to go new (or certified rebuilt) so as not to inherit someone else's problem. Why wait a week and pay shipping to probably have to revisit the same problem.
I am cheap, but this is one instance where being on the side of the rode due to electrical problems is not worth it!

[spyug]

As mentioned you need to properly diagnose the problem before attacking it willy-nilly.

By all means read the Stator Papers but there are a few things you can do first.

Get a digital multimeter if you don't have one already and also a battery charger which should be of the trickle charge type at no more than 2 amps.

Fully charge the battery and start the bike. Check the voltage across the posts at around 2000 to 3000 rpm. If the system is working, you should see high 13 into the 14+ volts.

If its in the 11s or 12s it could well be your rectifier and not necessarily the stator. The very next thing to do is run a line from the negative (black) lead of the rectifier to the negative post of the battery. Check the voltage again across the battery. This may have fixed your problem as it did on my 83 750E. This is a mod that is highly recommended .

If this didn't sort the problem then you should next perform the tests as outlined in the stator tutorial to determine if it is either or both of the devices that have gone wonky.

Once you get it figured, it is a good idea to fit a voltage meter to the bike so you can monitor as you ride along. You can usually get something at the autostores or electronics places like Radio Shack. Some guys go with a digital device with coloured LEDs but I prefer the old analog needle type gauge.

I have a charging issue with my XS that I am trying to figure out as well so you are not alone.....these old bikes always seem to have electrical issues

Anyway go at it methodically and you will figure it out.

Good luck with it.
Cheers,
Spyug.

[duaneage]

I have plenty of Honda RR kits at the moment, 40.00 delivered to the lower 48.

I would buy stators new as they can be degraded in use, the insulation suffers in overheated bikes.

[BassCliff]

The Stator Papers - five stars *****, two thumbs up, a must read, a real page turner! Better than fried chicken, more american than apple pie! freshens your breath and gets rid of acne! i was a 12.54 volt weakling constantly riding in semi darkness, now i'm up to 14.5 volts thanks to the Stator Papers!

Oh man! That's funny, but true. Thanks Mr. Eli69! :-D


Thank you for your indulgence,

BassCliff