Easy Stator/RR Replacement for '77 GS550?

[posplayr]

The single point ground collects return currents from
battery
harness
frame

and
then runs them to the r/r(-).

I have described this in a grounding thread. If you do this you minimize the voltage drops on the ground side between the battery and r/r.

you do not want to relay on the engine ground strap for a frame ground involving charging currents. There is typically 10 amps being supplied to the electrical system from the r/r. It only takes 0.1 ohms to get 1v drop. How much resistance does a dirty oily bolt on a painted frame have?

There has been a recommendation on the website going on 10 years to add a discrete ground wire between the battery and the r/r.

right now you are apparently losing 1.5 volts so the connections are dirty somewhere.

[tom203]

"What could possibly cause a consistent 2.4 volt reading from the stator? Does anyone have any ideas what might being going on here?"
this makes no sense, unless stator was internally connected wrong during winding. You still get .8 ohms lead to lead but no running output.

[posplayr]

"What could possibly cause a consistent 2.4 volt reading from the stator? Does anyone have any ideas what might being going on here?"
this makes no sense, unless stator was internally connected wrong during winding. You still get .8 ohms lead to lead but no running output.

I would attribute the 2.4 v to "auto scale" mode. Test on a house outlet first.

[Cassius086]

Here are some threads on grounding

http://www.thegsresources.com/_forum/showthread.php?140109-High-Performance-Power-and-Grounding&highlight=high%20performance%20grounding

http://www.thegsresources.com/_forum/showthread.php?220690-Ground-frame-locations

http://www.thegsresources.com/_forum/showthread.php?139115-Ground-Loops

[Steve]

I would attribute the 2.4 v to "auto scale" mode. Test on a house outlet first.

If it is, it would be an auto-scale problem on that meter.

I have never had a problem with auto scale on my old Fluke 77.

I am wondering if those measurements were 'open circuit' or was the R/R connected?

.

[posplayr]

If it is, it would be an auto-scale problem on that meter.

I have never had a problem with auto scale on my old Fluke 77.

I am wondering if those measurements were 'open circuit' or was the R/R connected?

.

"auto" is synonymous with "software".............;need I say more?


even if the R/R was connected you might see something closer 14V RMS. The stator voltage is tied to the rails of the battery.

[JE550B]

Right... so I stopped by the hardware store after work and bought a length of wire. Spliced the negative output from R/R and ran one wire to a bolt on the starter relay plate (frame) and one directly to the negative terminal on my battery. Last night I cleaned all of the positive wire connections between R/R and battery positive terminal. Voltage at battery key on motor off was 12.7. Voltage at battery with headlight on was 12.5. Voltage at battery @ 4000rpm was 12.6. Then I got frustrated and connected the R/R negative output directly to the battery negative terminal with no frame ground and the voltage readings at battery were exactly the same.

Is it possible that all of my readings at the battery are just my standing battery voltage and I am, in fact, not generating anything from the stator whatsoever? I can't even imagine how that would be possible unless the rotor wasn't spinning.

Now would be a good time for someone to jump in and remind me that the rotor doesn't turn unless you are in gear and I should be doing all of my testing with the motor in gear. Before I quit my job and go back to school to study electronics does anybody have any ideas about what might be going on? In the meantime I guess I'll go change the inline fuse and see if anything happens...

btw... auto scale on the multimeter works just fine on the wall outlet at home.

[posplayr]

Right... so I stopped by the hardware store after work and bought a length of wire. Spliced the negative output from R/R and ran one wire to a bolt on the starter relay plate (frame) and one directly to the negative terminal on my battery. Last night I cleaned all of the positive wire connections between R/R and battery positive terminal. Voltage at battery key on motor off was 12.7. Voltage at battery with headlight on was 12.5. Voltage at battery @ 4000rpm was 12.6. Then I got frustrated and connected the R/R negative output directly to the battery negative terminal with no frame ground and the voltage readings at battery were exactly the same.

Is it possible that all of my readings at the battery are just my standing battery voltage and I am, in fact, not generating anything from the stator whatsoever? I can't even imagine how that would be possible unless the rotor wasn't spinning.

Now would be a good time for someone to jump in and remind me that the rotor doesn't turn unless you are in gear and I should be doing all of my testing with the motor in gear. Before I quit my job and go back to school to study electronics does anybody have any ideas about what might be going on? In the meantime I guess I'll go change the inline fuse and see if anything happens...

btw... auto scale on the multimeter works just fine on the wall outlet at home.

If you review the "quick test" there are three voltages to measure the charging. Idle, 2500 and 5000. You only gave one so it is hard to tell much.

[JE550B]

Aha, forgot to differentiate. Idle: 12.5, @2500: 12.5, @5000: 12.6. This was after swapping the in-line fuse with a fresh one 5 minutes ago. Should I try running a discrete positive wire directly from R/R to battery positive terminal or would that be a bad move?

[posplayr]

Well with those numbers it suggests that there is nothing coming out of the stator and perhaps the 2.5vac you measured is correct. I would redo the stator phase b tests for leg to ground. If you are getting anything then you must have shorted out that new stator.

it might show with the ohm meter but it meas s pulling the stator cover again so I would double check.

[JE550B]

Okay, ran through the Stator phase B tests again. I got a 0.8 ohm reading between all pairs of stator output wires and an OL reading for each individual stator wire to many different frame grounds. I didn't fire up the engine again to test the voltage between stator output wires but the last time I tested each pair was consistently 2.5 vac. I guess the 2.5 vac fails the Stator phase B test but everything else is so consistent and seemingly behaving as it should that I can't help but feel like it's something else causing the problem.

Would it make sense to try these tests with a different battery? I've been using a new LiFePO4 battery so far. Should I try my tired old battery acid?

If I'm generating 2.5vac with the engine running, and there are no crazy noises, wouldn't that suggest that the rotor and stator have a reasonable relationship inside the case? I mean, maybe the stator was just garbage on arrival?

[posplayr]

If you have voltage leg to ground then you are shorted.


Link to Revised PHASE B of Stator Pages with discussion of testing methods:
http://www.keepandshare.com/doc/3977...4-pm-649k?da=y

[tom203]

"....maybe the stator was just garbage on arrival?"

This gets my vote! On ohm test, your meter gave "OL" on stator lead to ground (meaning no connection) which is good, though not conclusive..both of my failed stators still produced some output when they were shorted to ground, so if yours was/is you should see something above that 2.4 volts AC.

[JE550B]

If you have voltage leg to ground then you are shorted.

Turns out I've got 1.8VAC from each leg to ground at 5,000rpm...

Now, I thought I was being pretty careful during the stator install but everything is my first time on this bike so I may have done some damage without knowing it. Can anybody advise on what my next steps would be? If I have caused the short to ground myself is it possible that the stator is still good and I can fix it with the proper diagnostics? Do the measured numbers prove that this stator was bad on delivery and I should initiate a replacement process? Should I just forget about Electrosport stators and look elsewhere?

Thanks in advance for your help. Right now my rides are limited to how much courage I can summon up against a single battery charge.

[posplayr]

Turns out I've got 1.8VAC from each leg to ground at 5,000rpm...

Now, I thought I was being pretty careful during the stator install but everything is my first time on this bike so I may have done some damage without knowing it. Can anybody advise on what my next steps would be? If I have caused the short to ground myself is it possible that the stator is still good and I can fix it with the proper diagnostics? Do the measured numbers prove that this stator was bad on delivery and I should initiate a replacement process? Should I just forget about Electrosport stators and look elsewhere?

Thanks in advance for your help. Right now my rides are limited to how much courage I can summon up against a single battery charge.

Is sounds like there is a short across the three legs very close or the stator input. If you are sure the meter is correct, then open it up. There is not much else to do.

If there is no obvious damage call electrosport.