Strange...

[2Skunks]

I have been doing some reading and I can't seem to figure out why I have two regulator rectifier units on my 1979 GS1000. Its had some modifications prior to my ownership and I'm just starting to ride and learn about motorcycles.

The darn thing won't charge the battery. When the bike is running and I measure the voltage across the battery terminals it does not increase when the engine is revved.

I have been watching a couple videos on diagnosing charging issues and I found one in which the regulator rectifier unit has the same number and color wires as one of the R/R units on my bike, but the unit itself looked different than either one.

I plan to do some checking with the multimeter tomorrow, but I have a few questions too.

First, I know that if the battery is completely dead, I can give it a jump from another battery and it will run and drive just fine, all lights and signals functioning properly until I turn it off, and then it needs another jump. From this I gather that the stator must be OK, if it works anything like an alternator in a car. Is this a correct assumption?

Second, why would I have two R/R units? both are wired differently, but when I google the part number for each of them the both come up as Suzuki regulator rectifiers. It looks like one works on two phases and the other on all three. I think. I really don't know.
I read the primer, and I understand it, but nothing as to why I have two.

Also, Is there a way to find a testing procedure for the one R/R that I was not able to find a video about?

Thanks, I'm hoping to enjoy this thing for a long time. Other than this charging issue, it runs strong and is a blast to ride. It takes off like a scalded dog.

[Nessism]

Either some hack worked on the bike or you are mistaking what parts your bike has installed (separate rectifier and regulator).

Did you look in the service manual yet? http://members.dslextreme.com/users/bikecliff/

[2Skunks]

Hack, maybe, I don't know the bike's history. The R/R described in the service manual matches one of mine.
Both units are wired in, and both part numbers come back as regulator rectifiers.
Somebody put electronic ignition on it, and I think some other changes too. There is a black box about the size of a deck of cards sitting next to the battery and wired into the harness. I have no idea what it is. I'm sure some pictures may help. I'll take care of that when the sun comes up if anyone thinks it may help.
The second R/R unit looks like it's mounted exactly like you'd imagine a factory install to be mounted.
I'll get some pics up.

[tom203]

You likely have a seperate rectifier and regulator- they look similar.

"First, I know that if the battery is completely dead, I can give it a jump from another battery and it will run and drive just fine, all lights and signals functioning ... From this I gather that the stator must be OK, if it works anything like an alternator in a car. Is this a correct assumption?"

Don't assume, do a quick test and report results;

http://members.dslextreme.com/users/storagecliff/images/electrical_odd-n-ends.html#A20

[eil]

Hiya! Just a couple things to add to the suggestions so far... Please consider putting your bike (year and model) in your signature... there are many GS's and it will help people help you when asking questions.

I'll second Nessim's suggestion on reading up on the charging system in your manual. If you understand even a little bit about electricity, it should make sense. And there will be procedures for troubleshooting the charging system so you can locate the faulty component. One of the few things you won't find in there is advice to clean every electrical connection you can find before replacing anything. Many members here have had electrical issues disappear after thoroughly cleaning everything.

The bike may run fine with a bad R/R or stator (or both) but there may not be enough current left over to charge the battery. Mine was like that until I replaced the R/R.

[eil]

Oh, and forgot to mention: you can't troubleshoot a charging system accurately without a known-good fully charged battery. Get it charged up before doing any tests.