| Author | Message | ||
     Nateba |
I just swapped out a bad voltage regulator, and the bike has a brand new battery, purchased a week ago. The stator output is good (about 20v AC per 1000rpms.) I put the new V/R on today, and the battery with the bike on reads about 12.4 volts, and climbs only to about 12.7 when revved to 3,000 rpms, which is way below what the output should be. I'm at my wits end here. (2008 Ulysses) | ||
| Mark_weiss |
Are you measuring stator output only between the two terminals in the VR connector or are you checking between the terminals and ground? I made the mistake of checking to ground and thought that voltage reading meant that the stator was OK. Not realizing that voltage to ground meant the stator was shorted. | ||
| Nateba |
I checked between the two terminals on the VR connector. I'm getting about 20-28v per 1000rpms. | ||
| Lyonne |
The most likely cause and easiest check is for a grounded stator. | ||
| Ratbuell |
+1. Do ALL the stator checks from the manual. Sounds like at least one will get you an out-of-range result. | ||
| Tootal |
 There are three test for the stator and they all must be good or the stator is toast. You can pull the small window cover off your primary and take a whiff. | ||
| Electraglider_1997 |
Check the 77 connector or whatever it was replaced with on the 08' model year. | ||
| Griffmeister |
Yeah, it's still called a "77" connector but do the stator checks. An 08 is easy since there's only two wires. Step one: disconnect stator plug and measure continuity from each wire to ground (be sure you're on the stator side). This should be zero. Step two: measure resistance across the two stator pins. This should be 0.1 to 0.3 ohms. Step three: measure AC voltage across the same two pins with the engine running. The spec is 40 to 56 VAC at 2000 RPM but they do say that it's basically 20 to 28 VAC per 1000 RPM. So the manual says that all three tests should pass and they also have some load tests to further check the charging system. Of course at this point you kind of need a load tester. Let us know what you've got for readings. | ||
| Nateba |
I did all three stator tests. Continuity was good, resistance was within spec, and AC output was spot on. I dont have a load tester. I gave up this afternoon and brought it into a shop. The battery held its charge for the trip. On the way there, I got a few check engine lights and quite a few intermittent gas lights (with a full tank). I gave up. I'd like to trouble shoot, but I also just want to ride. I've had the bike for 8 months and it's been down half that. | ||
| Electraglider_1997 |
Froggy can't blame it on being a pre 08' year model. | ||
| Froggy |
Nah, I can just blame it on the lowest bidder quality parts used throughout all Buells since as far back as I can remember. Oh and if it was an 06 his bike would be in the shop for 13 months a year. Nateba - What battery did you get? It would be my prime suspect at this point, even if it is "new" that doesn't mean it is good. It could have sat on the shelf for a few years, or it could just be a subpar battery. Hopefully the shop figures it out for you. | ||
| Nateba |
Froggy- The battery is an OEM HD battery. I got stranded on the highway a few weeks ago and there was an HD dealership two exits down, so it was the easiest solution. The new battery tested good a few days ago when the bike started acting up again. That doesn't necessarily rule it out I guess. Hopefully I'll find out today or tomorrow. | ||
| Nateba |
So it was the stator. Apparently my testing skills missed it, but the according to the shop, the stator is indeed grounded. The shop told me that I might need a new V/R because the stator could have fried the one I just put in, two days ago. What do you think the odds of a ten mile ride frying a brand new V/R are? Is that all it takes? | ||
| Ratbuell |
Yep, that's all it takes. Electronics. | ||
| Luftkoph |
And since they will be putting in those high quality HD parts you may want to budget to have it done again in the future. | ||
| Nateba |
Haha, very true. Funny thing is, they made a point to tell me that if I went with an aftermarket part, they couldn't guarantee the work. I'll remember that in a month or two when I'm arguing that I just had the bike repaired. | ||
| Reepicheep |
Speaking as an engineer, I wasn't able to figure out any way a bad stator should be able to kill a voltage regulator. It's a shunt regulator, it should be at it's safest when the stator is toast. Which was *particularly* annoying, given there seems to be some evidence that happens. I could see it the other way around though... if the VR goes first, either failing open or failing closed, that could make the stator see much higher voltages or much higher currents. But don't loose hope... lots of people go a long way on bad stators and don't have to replace the VR. | ||
| Natexlh1000 |
I'm curious about how a grounded stator could kill a regulator too. Anyone have on that was killed in this way for me to pop open? I would think that there would be thermal evidence inside considering how much current is involved. | ||
| Ratbuell |
A grounded stator doesn't just put out a null voltage...it sends power down the ground leg. "Grounded" is a misnomer. "Shorted" is more accurate. | ||
| Tootal |
I was getting voltage spikes and blowing out my headlights. Changed the VR and it still blew headlights. Checked stator and it was shorted. Replaced stator and VR again. Been good ever since! | ||
| Reepicheep |
I could come up with several stories, but none of them were particularly convincing to me. Especially given how a shunt regulator works. Maybe what is really happening is that an intermittantly failing VR will kill a stator. So the VR is dying slowly, it causes the stator to completely die, which you replace, and then you later discover the VR is bad when it finally finishes dying. | ||
| Nateba |
Whatever the case, all I'm hoping is that once the new stator is installed, the VR that has only seen a handful of miles still functions like a new VR. I had to get the new VR shipped from an HD dealership in Florida and if I need another to replace it, there is a 3 week back-order from all sources. | ||
| Ratbuell |
Which is another reason I went aftermarket (Shindengen) - OEM for multiple other brands, easy install, and easy re-replacement should the need arise down the road. However...it's been running and charging like a champ since the install. Even my ORIGINAL battery from '06 continues to fire the ol' girl right up...with no battery tender since the install! | ||
| Tipsymcstagger |
Which of the Shindengen "kits" have you guys been ordering? Looks like there's one for $122 and two for $140. Other than the CB vs. fuse, I'm not sure I'm recognizing the differences. My bike is an '08. Tipsy http://www.roadstercycle.com/ |
