Question about switch to 7-wire Reg/Rect

[baz666]

Hello folks,
Thanks to everyone for their advice and links to the Stator Papers. Fantastic stuff that helped me track down the charging issue on my 83 GS750ESD. After reading through that material and following that incredible diagnostic chart I discovered that the Reg/Rect was finito.
I have a Reg/Rect from an 83 Yamaha XJ750 Seca and I know for a fact that it is working fine. It's a bigger, studier unit than the stock Suzuki item.
The thing is, the Yamaha Reg/Rect has 7 wires, 3 yellow, 1 black (ground), 1 red (power), 1 brown, 1 green.
I ran the three yellow wires to the three Reg/Rect yellow wires coming out of the harness. Then I ran the black wire directly to the negative pole on the battery. I ran the red wire to the red power wire in the harness. I've blanked off the brown and green wires and the bike starts but if anyone can tell me what I should do with those two wires (brown & green), I'd be much obliged.
thanks in advance,
baz

 

[almarconi]

One of them is probably a sense wire, that should be wired into your rear taillight. If you have a wiring diagram for the yamaha it would be easy to tell what the wires go to.

 

[baz666]

Thanks Al - and a big doh from me. Yep, I do have a Yamaha wiring diagram and I should have thought of that.
baz

 

[BassCliff]

Hi,

Make sure of the pinouts on the Yamaha regulator/rectifier unit. On the 7 wire unit I'm currently using (from a later CBR if I remember correctly) there are 2 "hot" outputs (red), 2 ground connections (green), and the three wires for the stator connection (yellow). There was no "sense" wire.


Thank you for your indulgence,

BassCliff

 

[Steve]

Hi,

Make sure of the pinouts on the Yamaha regulator/rectifier unit. On the 7 wire unit I'm currently using (from a later CBR if I remember correctly) there are 2 "hot" outputs (red), 2 ground connections (green), and the three wires for the stator connection (yellow). There was no "sense" wire.


Thank you for your indulgence,

BassCliff

Yes, some of the later Honda units like yours do have split power and ground wires, but the Yamaha does not do that.

.

 

[SqDancerLynn1]

Also make sure you have 12v/ battery voltage at the brake light if you use it for the 12v source It can cause charging problems if it is low

 

[baz666]

As I'd mentioned, the Yamaha XJ750 R/R has 3 yellow wires, 1 red, 1 black, 1 green and 1 brown. According to the wiring diagram. The 3 yellow are the stator, the red is the power wire, the black is the ground. As for the green and brown, here's where it got a bit confusing. The green and brown go to a connector plug which then appears to go into the wiring harness and meet a wire that goes to the front turn signals.
I'm just wondering what I need to do with the brown and green wires.
After splicing and soldering in the Yamaha R/R, the bike starts fine but I haven't had a chance to take it out for a ride and see if it actually charges.

And for BassCliff's site, here's one little helpful tip I stumbled across. On the site, it shows how to stick a small ratchet under the battery box to remove the R/R. On my bike, an 83 GS750ESD, the CDI unit, the fusebox and the solenoid all sit on a steel plate that uses two bolts to attach to the side of the bike. If you remove those 2 bolts, the entire plate slides forward and tips up so you can access the R/R very easily. It made the R/R replacement much easier.
But maybe this only applies to my bike, which appears to be a Katana derivative.

Something else that crossed my mind, with charging being a GS weak spot, would it be fairly straight forward to splice a volt gauge into the harness somewhere and if so, where could this be done?
Thanks to everyone for their help.
baz

 

[trippivot]

brown is going to be switched hot battery positive

I have my MMI Yamaha yama-pro books out and the color Green is commonly used as a headlight low beam circuit wire color.


I'm still looking for the R&R application schimetic you listed

back soon with more info.

 

[trippivot]

ok I have better information!!

the regulator rectifier you are trying to use will NOT WORK!!!!

the green wire is for the electro "field" as in electro magnetic EMS system.

You have a permanent magnet not a excited field charging system.

CB 750 honda XJ maxim you have to have a good battery to charge the battery.

on our 3 phase permanent magnet system it does not "need" the battery


The BEST R&R comes from a ZX6 "E", ZX 9all, zx11 all, EX 500 -all there are 5 wires and it stays very cool with the finned heat sink. yellow 3 ac leads. 1 red power. 1 brown switched hot. 1 black ground.


the XJ R&R no worrkie

 

[TheCafeKid]

ok I have better information!!

the regulator rectifier you are trying to use will NOT WORK!!!!

the green wire is for the electro "field" as in electro magnetic EMS system.

You have a permanent magnet not a excited field charging system.

CB 750 honda XJ maxim you have to have a good battery to charge the battery.

on our 3 phase permanent magnet system it does not "need" the battery


The BEST R&R comes from a ZX6 "E", ZX 9all, zx11 all, EX 500 -all there are 5 wires and it stays very cool with the finned heat sink. yellow 3 ac leads. 1 red power. 1 brown switched hot. 1 black ground.


the XJ R&R no worrkie

Tripp dude way to go the extra mile for a fellow member, looking all that up! This is part of what makes this place great! :clap:

 

[baz666]

Funny, the guy on the XJ site said the same thing. But I thought what the hey and spliced in the XJ Yamaha R/R. As I mentioned in another post, after installing the XJ R/R, I took the 83 GS750ESD out all afternoon, stopping many times. The bike restarted each time, no problem, which was the original issue that got me posting. Then I let the bike sit for a few hours. Then I took it out for a spin about half an hour ago. The bike started from the battery no problem. I stopped at a few places, got a coffee, ate a donut even. The bike started up again. I rode home and turned off the bike. Before rolling it into the garage about ten minutes ago, just for an experiment, I tried starting the bike and... geez... it started again. I did the 3,000 rpm test. It shows 14.7 and 13.5 at idle. After I got home, I also felt the XJ R/R now bolted and spliced to my GS750ESD. It was warm but not hot. Go figure...

 

[850 Combat]

Also make sure you have 12v/ battery voltage at the brake light if you use it for the 12v source It can cause charging problems if it is low

Yeah, I experienced that. It overcharged on my old GS1100G and cooked the battery. Rerouted it to the battery and have not had a problem since. Suposedly that can cause the battery to go flat when parked, but it has not.

 

[baz666]

Yeah, I experienced that. It overcharged on my old GS1100G and cooked the battery. Rerouted it to the battery and have not had a problem since. Suposedly that can cause the battery to go flat when parked, but it has not.

You didn't use a Yamaha R/R with 7 wires, did you?
Because that's what I tried and it overcharged the battery and blew a turn signal bulb.
Since Yam uses a field coil type alternator and Suzook uses a permanent magnet, I'm told the two are not compatible and cannot be adapted.
If you've figured out different, I'd love to hear about it instead of shell out for another R/R.
thanks,
baz

 

[BassCliff]

Hi,

As a reminder, if you need an r/r unit, Mr. duaneage has good, used, tested, Honda units for about $40. If you're in Canada it may be a little more, but still a great price. It's just another option.

Thank you for your indulgence,

BassCliff

 

[trippivot]

Amperage charges a battery NOT VOLTAGE.

Amperage current also turns the starter motor not voltage



ok you have 14.7 and 13.2 volts great but I have just a couple questions about the amperage rate of your "newly regulated" system. that have more to do with cooking or not cooking a battery

1. what is the total draw of your bike? ( -6~ -10amps?)
2. what R.P.M. is the break even ( 0.00 amps)
3. What is the total charging rate of your system? (+3~+7amps)
3.(a) does the rate taper off to under 1 full amp after 3~5 minutes of running? (0.05 amps)

My guess is at 14.7 ++ D.C.V. you are charging at 7 to 10 full amps and there is no regulating going on. You might want to keep an eye on the electrolite level.

I'm probably wrong.. but I'm bored.. and it is rainy..