OK, From the Electrosport fault-finding guide (http://www.electrosp...iagnosis-center), I did the cold test and am about to go for a ride and then the test hot, but this is what I've got.
2000 VFR, 11K miles
On the resistance test among the yellow stator wires, the fault-finding guide gives a range of 0.5 - 2.0 ohms. My readings either start at 0.4 ohms or start at 0.5 ohms and drop to 0.4. Not as definitive as I'd like, but wanted opinions on whether that was enough to declare the stator dysfunctional.
On the AC output at 5000rpm, I'm getting 58.9 for wires 1-2 and 1-3 and 61.2 for 2-3. Is that within tolerance for user throttle control and meter testing or is it another indication the stator is shot?
BTW, I don't know what any of these reading signal, but my symptom is when the bike gets hot, my voltage at battery is below 12.1.
OK, Off to get her hot and see how she likes probes then.
Ever stator Ive ever had fail, Ive never had to go past this test if its bad, Put your meter on the highest mega ohm scale, that way it will catch even the slightest of short. Check each yellow wire to ground, it should be totally infinite and not even the slightest of continuity.
11,000 miles is very early for an oem stator to fail, but the RR's on those bikes have issues with heat, thats why they made it bigger and moved it to the front of the bike on the 6th gens, and rare for them to fail.
59 to 62 isn't much of a float between phases. I wouldn't be overly worried about that. But did you check it with bike hot? If its still the same hot I'd be looking at the battery, how old is it? Might just be time for a new one.
The resistance test at the stator is now solid at 0.5 (go figure). But the AC test came back with 55 to 56v. That looked OK, but what was disturbing is the reading was totally unstable for 2 of the three wire tests. It would go from 40 to 38 to 20 to 55. The changes were so fast most of the time I couldn't tell what it dipped down to, but I was concerned that the voltage was consistently less than the cold voltage and it was fluctuating. Most time I do a reading, it stabilizes within a range quickly and may fluctuate slowly between that range.
I plan to replace the R/R anyway, but do these readings suggest I should do the stator too? I have both parts 'cause I just want this to be one job and be finished with it all AND RIDE!!!
My stator was kaput and I found that out by only doing the resistance test like spud suggested up above. This test is really just a continuity test and measures resistance between each of the three yellow wires, stator side, to ground (frame). If you have a reading, any reading, this is bad news and the problem is most evident when warm. Basically, if you are showing resistance it means there is continuity between the stator windings and ground. It sounds like most of the time it is just one of the wires that causes the problem, thereby giving you some charge, but not enough to sustain the system. This is confirmed when you crack open the case and half of the stator is darker (and crispier) in appearance than the other side.
I also changed my R/R (pre-stator :huh: ) in a Hail Mary attempt at making the problem go away. That was just wishful thinking though :laughing6-hehe: . Well, at least now I know what "Hope" and "Change" are good for without the hard facts to back it up.
Good luck with your trouble-shooting, I hope this helps.
+1 to the above. The fact pattern you mentioned ". . . but my symptom is when the bike gets hot, my voltage at battery is below 12.1" - and ". . . but I was concerned that the voltage was consistently less than the cold voltage and it was fluctuating." - points to a suspect stator. As things warm up they expand and resistance in the wires also increases. If the stator is crispy and has barely adequate insulation between some of the wires, as they heat up and come closer together they can intermittently short, you'll get issues similar to what you're seeing. If you've got the stator in hand you might as well knuckle down and install it. Then you'll have peace of mind. Be sure not to gouge the cover mating surfaces if you remove the gasket or you'll have leaks. I used liquid gasket remover and just wiped the old gasket off. Have someone hold the stator cover for you while you break the 4 stator retaining bolts inside the cover loose - that will make it much easier than trying to hold it with one hand and wrenching with the other. No sense being a few hundred miles from home with a dead bike.
At this stage, I think I'm going to replace the R/R and go for a ride. If the stator is outputting 55+ AC while hot that should be enough so my system charges. Even if it shorts intermittently, if the R/R is doing it's job, wouldn't it still be sending a charge to the battery some of the time? When mine goes bad, I'm consistently under 12.1 at idle - no charge being sent.
If it's the stator and not the R/R, then when I put the new one on, I shouldn't get any longer ride time before failure . . .
Unless, the stator is killing the R/R. How could that happen such that the new R/R masks the problem until the stator frys it???
"Even if it shorts intermittently, if the R/R is doing it's job . . . " This maybe a big assumption. What could be happening is when the RR heats up until it no longer RR's, doesn't work at all, and ceases to do it's job. Its like when your a kid and you find an electric motor. Connect a battery to it until it gets really hot, and then it shuts off. Let it cool down, and it usually works again.
A non-functioning RR happened to me with a brand new replacement. It was reading straight 12.1v at idle and 5k rpm (I found this out afterwards). I went about 7 miles on a total loss system, unknown to me.
Last thing, my Honda manual says 1-2 ohms of resistance on the yellow wires (on a gen 3).
After you do the The GROUND test on Megaohm scale, it will confirm good or bad, always start with that test, Ive seen nothing that you've done that test yet. Stators begin to lose voltage when they start shorting out, 99% of stators failure are due to shorting out of the winding(s) to Ground. Everyone always goes for voltage and resistance between the coils , those are secondary checks.
As far as secondary checks you have voltage and continuity between the coils, which is meaningless if you havent done the High ohms scale to Ground test of all 3 yellow wires.
Also, the intermittent stator operation may not be supplying power in a smooth wave form which the R/R may not be liking - sort of like an empty garden hose with a nozzle on it before it fills - the water comes out at the supplied pressure (volts), but it's spikey and choppy until it fills and smooths out. I'm no electrical expert, but it doesn't seem that could be good for the R/R if that's happening. If it were me I'd probably just replace it and be done with it. I wouldn't feel too bad - my 5th gen stator began failing at 7,000 miles . . .
Soooooo, I swapped in the new R/R and went for a ride. When I first turned it on, my voltage monitor went yellow. Gave it a bit of throttle and got green. Nothing too surprising seeing as everything was relatively cold. Was yellow at first two stop signs and green while riding. After that, solid green the whole way. :biggrin:
I'll keep watch on the monitor and do a hot ground test after my next ride since now I'm not worried about being stranded. I did the ground test cold/hot, but didn't do it with the Megaohm scale. I got nothing which is what you're supposed to get.
Hopefully, the R/R fix solves it for a few thousand miles or so. I'm keeping the stator for awhile, but may sell it after I'm more confident in my fix.
Any reason I can't store a stator indefinitely? In storage considerations I should have?
I'm sure others can speak more intelligently on storing the stator, but I'd put it in a zip lock bag and seal it. I think your only real enemy is moisture in this case.
[image: View Post]kaldek, on 06 April 2012 - 06:07 PM, said:
Unfortunately very few cheap/average meters go into the megaohm range.
Right, the $40 meter is good for basic stuff but not for testing things like this.
You really want to test it correct you need a Megaohmeter. One that can drive around 500 volts in to the coil. Even my $800 Fulke 189 meter could show a stator is good, when my Megaohmeter will show much different.