| Author | Message | ||
     Xbimmer |
So last week I started noticing my Kuryakyn meter started dropping to one green at idle, then at stop lights and long idle to yellow. Takes up to a minute of 2500rpm + to bring it back to two greens and if the fan turns on forget that. So let me know whether I understand the manual correctly. When I pull the stator connector from the Shindengen VR and poke each harness contact with the + lead, with my DVM -lead grounded to the engine, the scale should continue to read " 1 . " and not " 0.3+/- " right? This is what I get probing all three contacts. Yet when I run the engine at 2k I get consistent 35+/- VAC across all three contacts, 18VAC at 1k idle, which falls centrally in the specs per the book. I'm stumped at this point... can a grounded stator which would seem to be indicated still put out spec power?  | ||
| Electraglider_1997 |
Just watch the appropriate videos and they will answer your questions. http://www.roadstercycle.com/Roadstercycle.com%20V ideos.htm And maybe your meter is at fault if everything else passes the checks from the videos. | ||
| Reepicheep |
Look at the manual for your meter, they need some way to communicate "infinity". Or just hold the probes apart in the air in front of you and see what that says, that will be the "infinity" reading. Each stator wire to ground should read that same "infinity". If it doesn't, you are right, there is a stator wire shorted to ground and the stator has failed. That doesn't explain why you still see 35 volts between each leg though. Its possible that there is a short to ground, but it's one with a high resistance, and so you still have high voltage output but at a reduced power capability. Seems unlikely though. Confirm the resistance measurements again. Lead to lead (which should be some fraction of an ohm) and lead to ground (which should be infinity). | ||
| Griffmeister |
I believe someone else here had similar results just a few months ago. Indicated short to ground but still able to put out some voltage. Reep is probably right, a meter will pick up the slightest amount of continuity but you may not see the results until a significant amount of load is applied to the circuit. | ||
| Xbimmer |
Thanks guys I'll check it again tomorrow. | ||
| Reepicheep |
If you want to do a load test, you can just wire the stator output up to a household light bulb, just jumper the outputs to the plug. The higher the wattage of the bulb, the heavier the load test. Don't use an LED or compact florescent bulb.  See if the bulb is dimmer on one leg. | ||
| Xbimmer |
So wire in a 60-75 watt bulb, each leg to ground, or A-B/A-C/B-C? Thanks! | ||
| Reepicheep |
I believe you have to go A<->B, B<->C, C<->A. (Delta wound, not Y wound, or something like that I am trying to forget from long ago machines and power classes) For fun lets do the math for a 75 watt bulb.... 75 watts at 120 volts AC means the bulb has a resistance of about 200 ohms. If each stator phase can produce 40 volts at high RPM's, with that bulb as a load, the bulb should be dissipating about 8 watts. That's a decent load, but still a lot lower than the stator can produce. A 300 watt halogen shop light would be better, that's about 50 ohms, which means the bike would be dumping 30 watts during a load test. If you kept the RPM close to idle, the output voltage is probably close to 15 volts or so, meaning that if you hooked up an old headlight to it you could pull about 35 watts as well (I think that is what a headlight pulls normally). Just don't rev the bike that way or that headlight will have a short but exciting life. | ||
| Xbimmer |
Thanks Reep, sounds like something to dive into Saturday. Have a few H4 H7 bulbs around, would be easy to adapt for the idle test I'd think. | ||
| Natexlh1000 |
Just wire a couple in series and they'll tolerate more abuse. | ||
| Reepicheep |
Good idea Nate. That would be an easy way to add load. Plus, its just cool to see your generator light a light bulb. Don't ask me why.. | ||
| Lyonne |
I think in reality the self heating of the bulb is what limits current rather than the simple resistor idea. This just means you will see closer to the power rating of the bulb than the voltage would imply. | ||
| Natexlh1000 |
Well you would still want to put a meter on the bulbs to see exactly what it's doing. | ||
| Reepicheep |
Never thought of that Lyonne. Cool idea, you may be right. | ||
| Skifastbadly |
I was told there weren't going to be any math problems.... | ||
| Natexlh1000 |
As my EL201 teacher always said: "It's all just Ohms law."  | ||
| Callawegian |
Sorry to inform you but I believe Ohm's Law is E=I x R. Power Formula is P = E x I which is what your chart describes. Either way it can lead to a real electrifying experience. Will you be shocked if you make a mistake? | ||
| Djohnk |
The Indian sees the Vulture above the Rabbit ... I = V / R The Vulture sees the Indian and the Rabbit on the same level ... V = I X R The Rabbit sees the Vulture above the Indian ... R = V / I On the voltmeter I is Amperes, V is Volts and R is Ohms. That's Ohms law as my dad taught me 30 years ago | ||
| Motorbike |
Djohnk, that is something I've never heard. Easy way to remember Ohm's law. Thanks! | ||
| Xbimmer |
Situation worsened today to the point I'm parking the bike. Been riding it to work since above 2500rpm both greens on the Kuryakyn would light up, today though it never got above 1 green and it was gone by the time I got there. Pulled the headlight connector and it stayed on 1 green for the trip home. I have contacted Jack at Roadstercycle with the above info in my first post and he seems to think it's the stator. I contacted another well-respected expert here who says it may not be since it's putting out spec ACV even though I get continuity readings on all three legs to ground. About all I'm sure about is that at 1050 idle DCV's read 15.5V +/- from the VRR all the way to the battery cables, when disconnected from the battery. Fasten them back on and DCV's drop to 12 +/- at the battery, barely achieving 13 or so with increased rpm's. I'm leaning toward stator at this point but I'm too darn budgeted right now to be wrong... (Message edited by xbimmer on September 02, 2014) | ||
| Lyonne |
If it is any help my 2008 stator failed in a similar manner. A few hard starts, but it charged at higher RPM. Replacement of the stator revealed the ground. That was about 10k miles ago. Also the stator puts out AC. Lets start talking power factors and light bulb inductance just to complicate things beyond reason.  | ||
| Reepicheep |
If you have the '77' connector disconnected, and you are measuring the stator side, and are measuring anything less than a megaohm to ground from any pin... your stator or associated wiring is toast. Pop the derby cover and take a whiff if you don't believe me. Pretty odd that all three legs failed simultaneously though. Maybe the heat of one failing leg fried the other two over time. | ||
| Xbimmer |
Coupla nice blurry pics to illustrate. The readings are the same at the actual stator connector under the front pulley cover, this is the stator connector to the Shindengen VRR, negative lead is clipped to engine bolt. Not connected:  Touching the "B" leg, "A" and "C" results the same:  Doesn't stink under the cover, at least like I remember the first time 70K ago or so... | ||
| Electraglider_1997 |
Everything is too clean and that may be the problem.  | ||
| Reepicheep |
Is that the half of the connector and the wire going to the VR, or to the stator? | ||
| Xbimmer |
Everything is too clean and that may be the problem Don't I wish! That connector I'm probing is the 3-wire that connects to the stator connector under the pulley cover, here it's unplugged from the VR. The VR to battery leads are within that loom you see behind it, there is no longer a 77-connector in the mix. What do you guys think about that reading? | ||
| Electraglider_1997 |
I think .3 is the reading I got when I did those tests. Mine's fine. I have the same Mosfet. | ||
| Reepicheep |
Unless they radically changed the setup from previous years, you should see .3 or so ohms ***pin to pin**** (+/- .2 or so based on your meter and your probes). But pin to ground? It should be infinity (the left justified 1 in your first picture). | ||
| Xbimmer |
Well guess I'll be pulling the stator this w/e. I don't know why all three legs would show the same grounded value but I guess with electrics anything's possible. Maybe I'll luck out and the removed stator won't show any ground to itself, leaving me with absolutely no ideas at all... except that I have a good stator. Thanks for the help so far guys.  | ||
| Reepicheep |
That's the part that bugged me also. All three grounded at once? Maybe it was failing for a while, and you lost a leg, then another leg, and that caused some kind of thermal issue that fried the third leg. Or maybe you will learn something new that you will share with us and that we will all decide is obvious in hindsight. |
