GS1100G Road Runner Project

[londonboards]

Ride to Church and Oh No Not Charging!

It was a lovely day on Sunday. Temperatures up to 16 or 17 deg C. So the bike came out and we went for a spin in the lovely Kent (UK) countryside. I always wanted to stop and look at the church at Godmersham so I thought I would pay my respects.




I was very lucky that this church was at the top of hill. After driving for an hour and stopping for 10 minutes, I went to start the bike and ..........

SCREAM !!!

The battery was almost dead. Oh no not the dreaded stator / regulator / rectifier problem. I managed to roll down the hill and start the bike before I hit the main road by putting it in 2nd gear and bumping it. And furthermore, I managed to get the 5 miles home without it cutting out on me.

A huge feeling of dread engulfed me; I was finally going to have to read the Stator Papers. Anything electrical gives me a headache. This was not going to be very much fun.

[londonboards]

Visit to the Stator Paper Pages

I started on the Stator Tests (click to enlarge):




All I could get on this set of tests was a steady 13.4 volts when engine off and the same when it ran - whatever revs it was at. So I went onto section B of the Stator Tests:



I am not a proficient multi-meter user (much prefer the old ones with a gauge) so I get confused with settings, which holes to plug the leads in, which is + and which is - and the difference between a reading of 1 and a reading of -1. I couldn't get any readings to work on this test so I immediately assumed the stator was toast.

I am privileged to own 2 Suzuki GS1100Gs so my reasoning went that I could at least switch stators or use the other one as a test rig. So I took them both out of their motors.



The one on the right is original (I know because I have had the bike since new) and the one on the left looks like it has a different (replacement?) type of stator installed.





And I did all the tests again. Testing both of them in succession.



Having not got readings like this whilst the suspect stator was on the bike, I was surprised to find that all the readings were around 0.9 which is well within the prescribed range 0.5 to 2 ohms. Don't know why it wasn't looking like that when it was on the bike. Perhaps I had the wrong multi-meter setting or I wasn't getting a good connection.

So now it looks like the stator is OK. I would still like to see the thing kick out some volts when it was running to completely convince me though. Before I put it back in I will move onto the regulator/rectifier.

[hampshirehog]

Did you check you had a good earth to the electrics plate Richard? I've seen a good few GSs that are dead on the starter button, pulled off the side panel and wiggled that plate and they start.

[londonboards]

Did you check you had a good earth to the electrics plate Richard? I've seen a good few GSs that are dead on the starter button, pulled off the side panel and wiggled that plate and they start.

That has got to me my next step. Go through the connections one by one. And test the regulator/rectifier.

I hate electrics. Just want to do spannering!

Greetings

[tatu]

Maybe this will help you with some ideas if you need to replace the reg/rec if you need to. we can soon fix this.

http://www.thegsresources.com/_forum/showthread.php?t=197078

[JTGS850GL]

Make sure that none of the windings are shorted to to ground as well as checking between each wire. There should be an open between any of the wires coming from the stator and ground.

[eil]

Testing the stator/RR on the bike is really easy. If you disconnect the stator legs and measure the voltage at each pair (so, 3 measurements), you should get better than 75 volts AC at 5000 RPM. If so, the stator is good. Connect the stator back up and check the DC voltage at the battery at 5000 RPM. You should get between 14 and 15.5 volts DC. If you don't, your R/R is bad.

The R/R is more likely to die than the stator. Of course, checking to make sure all of the electrical connections are good and solid is a prerequisite to all this.

[londonboards]

Testing the Rectifier / Regulator with a Multimeter

So I'm following the Stator Papers testing procedure. I'm trying to determine if my charging problems are as a result of a faulty Regulator / Rectifier. I'm here:





I have the piece of kit off the bike and I am using a multimeter in the Diode Test position:

I get the same reading connecting the red multimeter lead to the red terminal and testing the three yellows.







Now the testing papers suggest that a positive result should produce a reading of 1.5v or better. What is a reading of 631? Is this reading .631 volts and and is the regulator / rectifier therefore below the 1v service spec? Is it functioning or not?

[cowboyup3371]

I might be mistaken but I believe you want your multimeter in DC volts for that test.

[eil]

That test doesn't make any sense. It's saying to put the multimeter in the "diode test function" and then uses volts for expected readings? There are a few problems with this.

The diode test function on most meters is more of a continuity test... if there's "continuity" (typically defined as resistance below an arbitrary threshold) between the two test leads, then beep. Otherwise, be silent. My meter shows the readings in ohms (I believe yours does as well), but assuming that some meters show it in volts, there's the additional wrinkle that different meters use different batteries. Some use a single 9V, some use an array of 1.5V cells. Again... that test, as written, makes no sense.

Furthermore, if this is meant to be a static resistance test, these readings can vary drastically among R/R models because their circuits are not identical. Even if they were, this test would only show you that some of the circuit was behaving properly, it is not a guarantee that all of it is.

My advice would be to test the stator and R/R on the bike per the factory service manual, the procedure for which I summarized in comment #82. I believe posplayr also has some good reference material in his signature which would be worth doing if you want go above and beyond.

[posplayr]

Stator/rectifier seems to be working.

13.3V at 3K RPM is actually quite low and possibly indicates that your have poor connections between the Battery and the R/R. With the SSPB that will be taken care of and you will not need to chase it down.

See the Quick Test in my signature for more details on voltage testing.

There is additional information available by doing this simple test which will help confirm any diagnosis I have done here.

[londonboards]

eil - that's exactly what I was thinking. I start to do some of these test (as a complete electrical rookie) and nothing makes sense. I tested in on the bike and get one set of readings then I test it off the bike and get another.

I'm glad that I am not going total insane!

Greetings

[JTGS850GL]

The R/R tests described above must be done with the R/R disconnected from the bike's electrical system. No stator or battery attached. If you try to do it with them attached you will get incorrect readings.

When checking the stator with a Digital Volt Meter (DVM) you need to disconnect the three stator wires from the R/R and measure resistance only, with the engine off. It takes 3 measurements to do verify this. Just randomly mark each of the 3 stator wires as 1,2,3. Them measure between 1 and 2, then between 1 and 3 and finally between 2 and 3. You should read between .5 to 2 ohms between each leg, but nothing higher then 2 or lower then .5 ohms. You should also measure each of the three wires to ground. Those readings should be virtually open. When checking the stator dynamically you measure AC volts with the engine running. Usually a reading between each combinational pair of wires (again 3 measurements) should read above 75V @ 5000K RPMs. This indicates a good stator.

Testing the R/R is a little more difficult. In the case of most shunt style regulators, you're really only testing the diodes but not the regulation capability. The diodes read continuity in one direction and not in the other. Even if you do test the R/R statically using the DVM, you're not guaranteeing that it’s good. Really, the easiest way to test the R/R is to first verify the stator output is good when operating. To do this you simply connect the R/R as normal and verify battery voltage. Assuming that the inline fuse and wiring is good and the battery is in good condition and charged, the battery should indicate a voltage above 14V but below 15.5V at 5000 RPMs it should also read above 13.8V at around 1500 RPMs. If not, then the R/R is bad and move on.

[londonboards]

Definitive Regulator Rectifier Testing for Dummies

I have spent a lot of time in the first instance, trying to find out how a multi-meter works and then figuring out how to use it to test my bikes electrics.

Unhelpful (to me) tutorials that state "test for open circuits" or "continuity of the windings close to the approximate resistance values" just make my head hurt. So I set about doing electrics research 101. I wanted to be 100% certain about what I was doing.

YouTube is the best for this if you have the time and patience. I looked at loads of of vids that came up after searching for; motorbike regulator rectifier testing. The result is that I found the definitive video. It's 15 minutes long and is a great tutorial on the job being done by this piece of equipment AND it also describes and shows how to use a multi-meter to perform the tests (if you don't want the theory, skip the first 12 minutes):

https://www.youtube.com/watch?v=r3mqG7f7qu8

A word of caution: this tests will prove a failed rectifier. It will not prove a working one. Nor will it prove that the regulator is regulating correctly. It only tests the diodes on the rectifier. If any of these diodes are not working then the rectifier must be replaced. If they all appear to be working and pass these tests there is a possibility (I am guessing) that the rectifier could still fail under load.

Applying these tests to my Road Runner bike and my Dad's bike's rectifiers, produced the following table of results:



So the rectifier on this bike is toast and the one on my Dad's bike looks bad too.

[tatu]

Richard, Just to ask, have you managed to resolve this problem?