SH775 install frustrations

[pdqford]

Okay guys, now for my next hurdle:

The wiring from the stator to my new SH775!

I suppose I could use the original 3 wires (Yellow, Blue/white, Green/white), ( by passing the headlight switch), and going directly to the SH775 but those wires look awful wimpy, and their connectors showed excess heat. Additionally, the Triump connector for the SH775 rectifier side looks like it expects a bigger gauge wire.

Or, I could do as Rich did and snip the stator wires near the stator, staggering the snips and splice in heavier wires and run direct to the SH775 rectifier side.
The Manual says that each stator wire can see up to 80 volts AC.
Anyone know how many amps the generator is rated for.?

The way I read the 1980 GS750ET wiring diagram in the Clymer Manual is that ALL current used by the electrical system flows through the main 15 amp fuse and I have never blown the main fuse so I’m guessing the generator is prolly 15-20 amps?

Maybe we have some “electrical Engineers” that could shed some light on these AC wires?

Thanks in advance ..............Jim

[Rich82GS750TZ]

I never said snip the wires close to the stator. Don’t do that. You want as few connections as possible and you want them in an area you can access. Put new ends on the stator wires. Put corresponding new ends on the 3 wires coming from the left (the 3-wire) side of the 775 triumph connector. Make good crimps. Tape them up. You shouldn’t need any new wire.

I think you're confused about something else as well. You've referred to the rectifier side and regulator side of the SH775.

Left side of the RR (it is a regulator and rectifier in one) has 3 wires that connect to the 3 wires of the stator, in no particular order.

Right side of the RR has 2 wires, Black goes to a good ground, SPG (single point ground), or battery negative, your choice.
Red (triumph connector's wire is more of a brown)goes to exactly where the red wire from your old RR was disconnected from. This then splits to a in-line fuse connection to battery positive, and into the harness.

[pdqford]

.....................................

I never said snip the wires close to the stator. Don’t do that. You want as few connections as possible and you want them in an area you can access. Put new ends on the stator wires. Put corresponding new ends on the 3 wires coming from the left (the 3-wire side) side or the 775 triumph connector. Make good crimps. Tape them up. You shouldn’t need any new wire.
Sorry about that Rich. You never did say to snip the stator wires close to the stator. I was wanting to run a heavier wire up to the SH775 in case they were too light and contributing to the overheated original connectors. If the original stator wires are adequate I may be able to run them straight into the Triumph connector after snipping the connectors off as I have the Triumph connectors to put on the ends of the stator wires. That will depend on IF the original stator wires are long enough to reach the location of the SH775.

I think you're confused about something else as well. You've referred to the rectifier side and regulator side of the SH775.


Left side of the RR (it is a regulator and rectifier in one) has 3 wires that connect to the 3 wires of the stator, in no particular order.
Sorry about that also. I use the rectifier side to indicate the 3-wire connector of the SH775 (where the three stator wires AC current gets rectified in to DC current) and the regulator side to indicate the 2-wire connector where the regulated voltage emerges from the SH775.

Right side of the RR has 2 wires, Black goes to a good ground, SPG (single point ground), or battery negative, your choice.
Red (triumph connector's wire is more of a brown)goes to exactly where the red wire from your old RR was disconnected from. This then splits to a in-line fuse connection to batter positive, and into the harness.
Correct. I don't have the full Triumph lead, just the Triumph connectors and Triumph ends. Ill have to improvise when (IF?) I get to that hurdle.
Thanks again for your help and guidance.

[Nessism]

It will do no good to take a 16 gauge stator lead, and upsize it before attaching to the Triumph jumper. The default will be the smallest element, which is the original stator wires. Realize, of course, that these original wires are more than large enough to carry the current the stator can produce. For the attachment, I'd solder them. That's the lowest resistance attachment method.

[Rich82GS750TZ]

And I usually defer to Ed on such matters. However, I’m not the best solderer, so I went with the best crimp connectors I could find.

You will want to trim those stator wires back past any verdigris (green) corrosion to fresh copper before either soldering or crimping on new connectors. Some do both.

Which leads me to. Have you tested your stator output? Do you know that your stator is still good? What usually happens is the connectors melt, corrode, causing resistance and takes out the stator. Some people will replace the stator at this point prophylactically, even if it tests as good. Just food for thought.

[pdqford]

. Realize, of course, that these original wires are more than large enough to carry the current the stator can produce. For the attachment, I'd solder them. .

Thanks for confirming that Ed. I wasn’t sure the original stator wires were up to the task.
Since they are adequate, hopefully, I will end up with no splices and the only crimp & solder joint (belt and suspenders :-) will be at the Triumph connector.

[pdqford]

Which leads me to. Have you tested your stator output? Do you know that your stator is still good? What usually happens is the connectors melt, corrode, causing resistance and takes out the stator. Some people will replace the stator at this point prophylactically, even if it tests as good. Just food for thought.

Last time I tested the stator output all three legs read 72.x ohms.
Not quite up to spec but, with these changes, should be enough to keep the battery up.

P.S. Monday, 7:30AM, I go in the hospital for a “chemically induced” nuclear stress test (what ever that is)!
Worrying about my Zuki keeps my mind off other things.
So, I appreciate all the help and advice the forum provides.

[Rich82GS750TZ]

Jim, best of luck with your medical issues. Take your time with the bike. I've always found shop time on the bike to be a great stress reliver and escape from stuff.

[Grimly]

Last time I tested the stator output all three legs read 72.x ohms.
Not quite up to spec but, with these changes, should be enough to keep the battery up.

Better to check the stator leg to leg at 5000rpm, should be 70-ish V AC.
I had one that checked out fine on the ohmeter, but was defective under load.

[pdqford]

Better to check the stator leg to leg at 5000rpm, should be 70-ish V AC.
I had one that checked out fine on the ohmeter, but was defective under load.

My bad again Dave. I should have said all three legs read 72.x VAC, not ohms

[pdqford]

Jim, best of luck with your medical issues. Take your time with the bike. I've always found shop time on the bike to be a great stress reliver and escape from stuff.

Thank You for the kind words, Rich.

[Grimly]

My bad again Dave. I should have said all three legs read 72.x VAC, not ohms

Should be good to go, then.

[pdqford]

I have studied the wiring diagram for my 1980 GS750ET.. It seems to me ALL the current to run the bike must travel up to the ignition switch AND THEN back to the glass fuse block, and then from THERE it can then go out to the various circuits. No wonder I was experiencing recurring voltage drops. Seems like I was always cleaning connections and polishing those glass fuses.

Okay, now I have sketched out (see below) how I plan to rewire the left side electrical panel on the bike. I think with these changes the trip up to the ignition switch and back will have a minimal amount of current on that leg. (When the bike is running that circuit will only have to support the current to energize the new 30 amp relay (about 0.2 amps) or if the ignition switch is switched to the park position to run the 8 watt tail light (about 0.7 amps)).

Just wanted to know if I am overlooking something on this project so looking forward to hearing comments.

(The most frustrating task so far is trying to get my diagram loaded on flickr and attached to this post! I have given up trying to rotate the picture so it is easier to view.)

[pdqford]

Okay, I found if I take a picture of my modified wiring diagram with my ipad, and mail it to my laptop I can get a better picture loaded to flickr that is right side up and I *think* can be enlarged by clicking on the picture to make it even bigger when viewed in the forum. Here's hoping!

Diag 2.31 by pdq ford, on Flickr

[TheAlt]

Well nuts. I was going to post to a new thread, but this one is just too timely.

I have a 82 GS 450A and made an aluminum bracket to replace the old rectifier.
This bumps out the new one about 1/4" of an inch.
Then I mounted it to the new bracket.

The relay. I made a couple of bushings to drop it about 20mm and used new bolts.