Could a sh775 kill a stator?

[Guest]

I got a used sh775 and installed it today and upon startup at idle I was getting over 13 volts. 14.1 at 4000 rpm's. I figured I had fixed the charging issue. I checked it again tonight and it was not charging. I checked the ac output on stator wires and 2 were around 50-55 volts and one had nothing. Could the rr killed my stator?

Before I installed the new rr I was getting over 80 volts on the stator. I hooked 3 yellow wires to the grey plug and red on inside black and ground on outside of the black plug. Any ideas? I don't want to get a new stator and have same result.

[posplayr]

First question: Is it a real Sh775?
Second question: how long did you run the stator with a shunt R/r?

Regardless of the answer it is extremely remote that the sh775 caused any problem. Like you just won the lottery .

[harman84]

The rr has the right numbers stamped on the end so I think it is oem.
I probably ran it 15 minutes. I am going to pull the stator cover off and see if the stator looks burnt up. I did notice the rr was warm to the touch. it wasn't hot though. I believe my wire were hooked up right.

[harman84]

So I went and checked the charging system again after the bike sat for a few hours. upon first starting the engine I was getting 14.1 at 4000 rpm. The bike idled there for 2 minutes tops. I checked it again at 4000 rpm and was under 13 volts again. Not sure what to think now. I am going to check again this weekend when it stone cold.

[posplayr]

The stator is probably going out. You did not mention doing the leg to leg tests at 5K RPM. These are usually the best tests.
You might get a better indication .

And here are some updates with background to the Phase B tests that focus on the stator alone.

A revised test is at this link; The actual test is on Page 6 of 9. We added the leg to ground AC voltage test as this helps isolate insulation breakdowns to ground using the relatively high 60-80 VAC stator voltage when it is open loop.

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

[harman84]

Thanks. I will look at the revised tests some more tomorrow. I looked real quick and my head was starting to hurt. I sure its not that hard to figure the test out. It just was a lot to take in tonight.

[posplayr]

exact same test as "leg to leg" just put one lead to case ground; You should see zero VAC whereas leg to leg is 80VAC.

You are checking for any evidence of a short in the winding that might occur at many places.

[DohcBikes]

My brother has been a service writer for a polaris dealership for several years. They replace the exact reg/reg you guys recommend on this site all the time because they regularly fail and ruin stators. it's not any better than any other, and arguably worse. For the past year they have been recommending mosfet regrecs (aftermarket, which is not their norm because they are a dealership) and have concluded that they are superior.

[posplayr]

My brother has been a service writer for a polaris dealership for several years. They replace the exact reg/reg you guys recommend on this site all the time because they regularly fail and ruin stators. it's not any better than any other, and arguably worse. For the past year they have been recommending mosfet regrecs (aftermarket, which is not their norm because they are a dealership) and have concluded that they are superior.

That is certainly an interesting comment. I know there are some bikes where there are recommendations for MOSFET R/R's when the stators DO NOT burn up. But if there is any evidence of burning stators then a SERIES R/R is the solution which can be one of a few on short list. The SH-775 is the cheapest.

I don' know if there is even one case where someone has had a stator failure using a SERIES R/R except if the stator had already been run using a shunt R/R or the stator had suffered a mechanical failure after many miles.

Maybe someone has their part numbers wrong?

[DohcBikes]

They regularly fail, and they ruin stators. He and I just had a long discussion about it, and how the solution is mosfet

shunt r/rs work fine in many bikes. oem suzuki stators and regs are exception, always have been

[posplayr]

They regularly fail, and they ruin stators. He and I just had a long discussion about it, and how the solution is mosfet

shunt r/rs work fine in many bikes. oem suzuki stators and regs are exception, always have been

If your are speaking of SH775's there is plenty of evidence that the statement above is incorrect as related to GS motorcycles. Are you referring to Polaris applications?

[tom203]

They regularly fail, and they ruin stators. He and I just had a long discussion about it, and how the solution is mosfet

"regularly fail...."

I've been using a sh-775 for 4 years now mated with a previously used stator- no problem at all. I'm sorta skeptical about Polaris having issues with the sh-775 , unless it involved stators having a greater output than shindengen's specs.

[DohcBikes]

Be skeptical. All i can do is offer facts. They fail all the time. As much or more than others.

I mean, right here we are in a thread where the reg rec has likely caused an issue. Id expect more soon.

Mosfet is the way to go.

[cowboyup3371]

I will also disagree with your statement that the SH775 fails more than any other. I have owned my bike going on 7 years now and put almost 20000 miles on it since I bought in. In the first 4 years I owned it using a shunt regulator I had to replace the stator at least twice. Since I replaced the R/R in 2014, I have not had a single problem with my stator and charging continues to stay where it should be.

Yes, all mechanical things fail but to say these R/Rs fail more than the shunt regulators without providing actual documented proof does not lend credibility to your statement.

To point to this guy and say - see, it's crap - doesn't take into account the fact he said he replaced his old one with a used one. We also do not know if the stator was already burned out or at the least on its last legs. I think a better recommendation would have been to replace the stator and monitor both for awhile before declaring the R/R as the cause.

[DohcBikes]

Cool.

...MOSFET...

Too busy working on my bike to care. Have a good day!