Battery/Charging Issue. Need Help
Last edited by ironoxide; Apr 23, 2013 at 11:59 PM.
Scale on DC Volts, around 20V max voltage scale. Nominal readings are given in brackets. Check voltage across battery terminals (12.8). Turn bike on. Check voltage (less than previous, ~12.0+,depending on headlight, accessories). Start bike and let idle. Check voltage(could be 12.0 to 15). Rev to about 2500. Check voltage (should be more than observed with bike on but motor not running, and more than with bike off.Ideally between 13 and 15.) Turn high beam on. Should be about the same, giveortake a little. If the voltage is over 15 or 15.5-ish with a headlight on,I'd consider replacing the regulator and/or checking all grounds (battery to frame, regulator to frame in particular). If the battery voltage with theheadlight on, bike not running is less than around 11.5-ish, I’d replace thebattery. If it’s 10, it’s past its prime.
If you pass the above tests, your system is most likely fine, including the regulator and stator. If you don't pass, then:
Bike off. Meter set on Ohms, medium-ish scale, like 20K or 200K Ohms max scale,depending on your meter. Pull stator plug. Ground the meter black lead to a good chassis ground, like a bolt or even the battery negative. With the red lead, touch a different part of the bike, like the engine case at an unpainted part or another bolt. Meter should read low ohms, like 0. If it doesn't, you didn't ground the black lead. With the red lead, touch each contact on the motor side (stator) of the plug (the part stuck in the case). Depending on if your case has a male or female plug, if you can't see the metal part/pin of the plug, you can put a paper clip in the hole and touch the paperclip with your meter red. Meter reading should be infinity on all pins. If it isn't, your stator is shorted to the case, replace.
The following is for single phase systems. I don't have a multi-phase and haven't had to diagnose anyone else’s, so I haven't dug into those systems.
Set meter to lowest ohm scale, like 200 Ohms, typically. (Note: Not 200K ohms).Check resistance between the two stator plug pins. Should be fairly low. My Book says 0.2-0.4 ohms. The spec is in your shop manual. If it is infinity,stator is blown open. If it is 0, stator is shorted to itself.
Set meter to AC Volts, 100V scale. Attach each meter lead to a stator pin. You may need to rig up some type of temporary plug. It is important that nothing can short to ground or to each other accidentally, or you will blow the stator if it wasn't blown before. An old plug off of your last regulator is a good way to do it, but, get creative and be careful. I can do it holding the leads on the pins once the bike is running, but I don't like to. Start bike. Voltage should vary with engine speed. Specs are in your shop manual, but 35V at a couple thousand RPM is probably about right. My book says 19-26 V / 1K RPM.
If you passed that stator test and failed the first test, your regulator is shot. If you failed any part of the stator test, replace both regulator and stator.
Last edited by texashillcountry; Apr 24, 2013 at 05:41 AM.
Best of luck, and here is that link: https://www.hdforums.com/forum/evo-c...positions.html
Use caution to not short the battery when working on these connections.
I also rewired my ignition switch to be able to start and run the bike without the drain of the lights pulling current away from the starter and ignition. It was very simple and I'll even ride without lights to give the battery a full re-charge on days I'm doing a lot of errand stops and multiple daily restarts.
Follow the Dr. Hess tests and you will find your problem. If it is the stator, I recommend that you also replace all of your inner/outer primary seals, race and bearings while you are doing this. The parts are cheap, but very labor intensive, so since you got the everything apart......
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After waiting almost 2 weeks for the dealership to get my voltage regulator in I finally got it installed today. Bike is back to charging as it should. You can see in the photo the cracks in the back of the old regulator. I used the testing you guys mentioned above to narrow my problem. Thanks to all that contributed. You guys saved me from just throwing money at everything to fix what ended up being one thing. Of course the past two weeks have been 70's and sunny while waiting for parts, but for the weekend we're looking at rain, and dips into the 50's for highs. Stupid northeastern Ohio. Thanks again.
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The problem with keeping a bike on a charger is that it can mask a charging system problem, the bike may start fine in the garage because it just came off the charger, but then you get down the road and try to restart the engine after a stop, and then you are stuck.












