would you replace a stator with these readings?

[don_gibb6512]

Will test again using a different meter that has a fixed low ohm setting of 200. I take it that readings across two stator wires should equal twice the reading from any one wire to ground because reading across two wires adds the resistance in the series circuit.

 

[Matchless]

If the stator tests show a short or very low resistance to the case when testing on the three AC wires, you will most likely get it on all 3 wires.
If the windings on the stator show no signs of burned or melted insulation then you very likely have a solid copper wire making to ground outside of the actual winding area.

Have a close look at the 3 tails that are soldered together, sleeved and tucked in behind the coils. Also have a close look at the 3 tails on the front going to the 3 AC wires. If any of them touch a corner of the stator frame, the insulation can be damaged and could cause the short to ground.
If so you could save a stator by moving and/or sleeving those wires and also fitting 3 new AC wires at the same time.

Hope this helps

 

[Graham]

Maybe you need to rewrite the stator papers, obviously Pos got it all wrong.

I?m not saying posplayr is wrong. I?m just an old school motorcycle mechanic with old school ways.

 

[tkent02]

I?m not saying posplayr is wrong. I?m just an old school motorcycle mechanic with old school ways.

Sell parts, that's the job.

 

[don_gibb6512]

If you read any voltage (while running and unplugged) from stator wires to ground (casing) buy a new stator.

I'll try this in addition to retesting with different meters. Hadn't considered doing this while the bike was running. Thanks.

 

[don_gibb6512]

It does help and thanks. If I still get a reading using the other meters that I borrowed yesterday, I'll open up the case and take out the stator. Really wanted to avoid that this late in the season.

If the stator tests show a short or very low resistance to the case when testing on the three AC wires, you will most likely get it on all 3 wires.
If the windings on the stator show no signs of burned or melted insulation then you very likely have a solid copper wire making to ground outside of the actual winding area.

Have a close look at the 3 tails that are soldered together, sleeved and tucked in behind the coils. Also have a close look at the 3 tails on the front going to the 3 AC wires. If any of them touch a corner of the stator frame, the insulation can be damaged and could cause the short to ground.
If so you could save a stator by moving and/or sleeving those wires and also fitting 3 new AC wires at the same time.

Hope this helps

 

[don_gibb6512]

Going to bed. Gonna shoot pool tomorrow night and do something that I'm actually good at. Cheers.

Didn't sleep a wink Sunday night and got clobbered at pool last night. If anyone wants to get in some kicking, now's the time to do it. Geesh.

 

[don_gibb6512]

Test results with an Metex M-3800 digital multimeter set at the 200ohm range. Stator wire-wire came out to 1.1, 1.2 and 1.1. Wire-ground test came out to the SAME readings 1.1, 1.2 and 1.1.

So, the first test using the Radio Shack meter results were basically .4 on both sets of tests and this time it's basically 1.1 on both sets of tests.

Other than the meters are obviously using different range settings, does anyone have any input????? I won't be able to yank out the stator for further inspection until this weekend.

Thanks

Don

 

[tom203]

Test results with an Metex M-3800 digital multimeter set at the 200ohm range. Stator wire-wire came out to 1.1, 1.2 and 1.1. Wire-ground test came out to the SAME readings 1.1, 1.2 and 1.1.

So, the first test using the Radio Shack meter results were basically .4 on both sets of tests and this time it's basically 1.1 on both sets of tests.

Other than the meters are obviously using different range settings, does anyone have any input????? I won't be able to yank out the stator for further inspection until this weekend.

Thanks

Don

You edited your earlier post to say you get only 12.08 volts at 5k rpm. This means your charging system ain't producing.
This is the result I got when my stator shorted to ground; but my r/r wasn't damaged. (original r/r)
As far as stator wires to ground test- It was asked before..."U are measuring resistance between the legs to ground when the stator wires are open right?" ???

 

[don_gibb6512]

You edited your earlier post to say you get only 12.08 volts at 5k rpm. This means your charging system ain't producing.
This is the result I got when my stator shorted to ground; but my r/r wasn't damaged. (original r/r)
As far as stator wires to ground test- It was asked before..."U are measuring resistance between the legs to ground when the stator wires are open right?" ???

Yes but I am getting 64v AC out of the stator at 5K rpm's though. I work in the Dept. of Electrical & Computer Engineering at the Ohio State University and I've asked one of our Power Faculty to think about this. The fact that I'm getting resistance through the winding yet AC output is odd at best. That I'm getting the same measurement across the wires as wire to ground doesn't make any sense either. Wire - wire should be twice wire to ground. The RR had a burnt connection in the ground wire and test results on that determined that the Rectifier circuit went bad. I had an independent test done on the RR to verify my findings. I haven't ran the resistance test on the stator, wire to ground while the bike is running yet but I honestly don't see why that would be different than if the bike wasn't running. But then, I'm NOT an electrical engineer so I always assume there might be something I'm missing.

Thanks for the reply. Don

 

[don_gibb6512]

Looks like I'm going to pull the stator and take it to our lab for further testing. Better safe than sorry. I'll post the results, probably at the end of next week.

 

[bakalorz]

Yes but I am getting 64v AC out of the stator at 5K rpm's though. The fact that I'm getting resistance through the winding yet AC output is odd at best.

Actually thats not odd.

When its not connected to the R/R, the stator floats with respect to ground.
A short to ground in the stator (or stator connection wires) won't prevent the windings from making voltage relative to each other (which is the 64 V ac measurements)

However, when the R/R is connected, the short to ground would then cause problems, since the stator is no longer floating.

If you can find a pinched wire or whatever else is grounding out your stator, you can fix it, otherwise you will need a new stator.

---

BTW, doing Graham's test, and measuring the voltage generated between the stator connections and ground with the bike running (and the stator disconnected from the R/R) can help track down where the short likely is:

If you get three equal readings (likely to be sin(60)*64= 55 volts) then the short is probably where the three connectors join to make a Y.

If you get two readings of 64 volts and one of Zero, than the short is on the output of the winding reading zero (quite possibly where it exits the engine)

In either of these cases, it's probably possible to repair the stator without rewinding it.

If you get two high but equal readings and one that is much lower (but not almost zero) then it is probably in the middle of a winding.

In this last case it's probably NOT possible to repair the stator without rewinding it.

 

[bonanzadave]

Looks like I'm going to pull the stator and take it to our lab for further testing.

If the Stator is putting out why pull it ?

I'm NOT an electrical engineer

You dont need to be. There are 3 combination of stator wires to check. If you get good AC voltage on all 3 combinations youre golden. Stator wires must be completely disconnected from the RR wires / connectors and I would cut off any connectors on them to do the test. Clip the meter leads on 2 of the 3 stator wires.

wires A to B = 65VAC @ 5K RPM

wires B to C = 65VAC @ 5K RPM

wires A to C = 65VAC @ 5K RPM

 

[Matchless]

When its not connected to the R/R, the stator floats with respect to ground.
A short to ground in the stator (or stator connection wires) won't prevent the windings from making voltage relative to each other (which is the 64 V ac measurements)

However, when the R/R is connected, the short to ground would then cause problems, since the stator is no longer floating.

If you can find a pinched wire or whatever else is grounding out your stator, you can fix it, otherwise you will need a new stator.

This is correct!! And can cause a lot of confusion...!

 

[don_gibb6512]

This is correct!! And can cause a lot of confusion...!

Confusion is right. I think I'm going to order a new stator but I'm still going to take the one I've got in to our lab for further testing.

Thanks much.

 

[posplayr]

Confusion is right. I think I'm going to order a new stator but I'm still going to take the one I've got in to our lab for further testing.

Thanks much.

When it comes to stator tests, anything short of a loaded test (measuring current or voltage at 5K RPM) is circumstantial at best.

 

[Guest]

My two cents.

My two cents.

Just reading the threads about the stator and RR unit, Posplar is no way wrong, he has some of the best replacement instructions I've seen in the forum. I should know. I have replaced my stator 7 times now and 3 RR units on my 1980 GS750E. Most of the problem was crappy replacement parts to begin with, I would only get about 3 years max off a system before it burned out. The last time I replaced them I used the Electrix's stator and RR unit, this one lasted for about 8 years for once till this last burn out. I then followed Posplar's recommendations with the Compu-Fire series type RR and a new electrosport stator and did his recommended wiring, I saw an difference right off off the bat, the wiring and RR unit were way cooler then I have ever seen them in the 30 years of owning the bike. I know for a fact if the stator is only putting out 65VAC its time to change that sucker, it is starting to die, a new one will be throwing a charge of 75-80 VAC and replace the RR unit with the Compu-Fire, remember you get with you pay for.

 

[tom203]

Actually thats not odd.

When its not connected to the R/R, the stator floats with respect to ground.
A short to ground in the stator (or stator connection wires) won't prevent the windings from making voltage relative to each other (which is the 64 V ac measurements)

Let's see if I'm following this "float". What you're saying is that a stator wire could be grounding out, but when we measure between any two stator leads, we don't notice this cuz we're not measuring between a stator wire and the ground. OK, makes sense. So we can't just rely on a decent ac output test of 60 volts on all 3 stator leads- we have to ohm check the stator to ground.

 

[don_gibb6512]

Well, I'm going with Duane's RR and an Electrosport stator. Our lab can test the stator under load (current applied) so we'll see what comes of that. It may be that the Stator papers need an appendix to accommodate situations like what I've run in to. If so, I will humbly request as such from Mr. Posplayr.

 

[posplayr]

Well, I'm going with Duane's RR and an Electrosport stator. Our lab can test the stator under load (current applied) so we'll see what comes of that. It may be that the Stator papers need an appendix to accommodate situations like what I've run in to. If so, I will humbly request as such from Mr. Posplayr.

I really can't take too much credit for the Phase B (stator tests) and Phase C (R/R tests) parts of the stator pages. I only modified the Phase A. However, we have had a few instances in the last couple of years where people have run into stator issues where they try to apply the stator tests and they get confusing of false results and end up wasting a bunch of time. I think it was Psyguy who had a temperature dependent stator problem he wrestled with for quite a a while before he finally just changed the stator and got over it.

So while there are so die hards (who will want to use an ohm meter even though it really is a not a good choice), it may be that the best test solution for a stator is really to just :

a.) test the R/R instead (to rule it out)

or

b.) replace the R/R with a know good (also to rule it out)

and go back to the start of the stator pages and if the problem persists change the stator.


The reality for stator is as I posted before most of the stator tests are circumstantial. Few of the tests are conclusive if all you have is a AC volt meter and a ohm meter.

When I have time I'll try and look at rewriting the other phase to reflect these realities. Swapping parts can be just as effective as testing for a defective unit and in the case of the stator actually much better to just swap parts.