Still probably the Voltage Regulator. Hope its not stator. If it is stator, Replace BOTH. And do it before it destroys the Battery. Them suckers are expensive. My 08 Nightster kept "dragging" (started slowly when hitting starter). Had to charge it a few times on slow charge. I never bought a trickle charger but they will kept it topped off. One day, I tried to start it up, and it wouldn't after sitting for about two weeks. So, instead of putting it on the charger, figured I would roll start it in 2 gear down a little dip on our dead end paved road. It would of and could of started, BUT being in such a hurry as I was late for an appointment and wanted to ride my scoot, I forgot to turn the "run" switch on. So, being at the end of the dip(mild incline) and unable to push it back to the yard, I did the stupid thing. Jumped it with my truck battery. Now I know there is a huge difference in the AMPS. I opened the battery case and slid it out. Pulled truck up to her and shut it off so it wouldn't be so HOT of a jump. Put my ground clamp on the ground post of bike. And just slightly touched the positive to the bike battery. She fired right up. Left her running and returned the truck to the house. Got on her and took off, and about 8 or 10 miles away, I noticed battery and fuel lights and the engine light (3 lights lit). Turned it around and took her home. Pulled battery out totally and put on 2 amp low charge. 3 hours later, it said 100% charged. Put back in and went down the road less than 1/4 mile and all lights lit again. Repair guy at the stealer said it shouldn't of hurt anything. "probably just the battery" Was the original one from end of '07. Figured 5 years not too bad. More than a hundred bucks, but I said ok and took it home and installed it. After riding less than 1/4 mile, lights back on. Took it to my repair buddy and he checked it out. The stator was blown out. One of the "posts" on a winding was FRIED. He asked what happened, as he had never seen one that bad before. He said since the regulators aren't that expensive and time consuming, it is better to replace BOTH. He shopped around and found me a cheaper price than the Stealers selling price for both, plus he installed a head lamp that I purchased already , all for about 245 Bucks including labor. What a pal! GOOD LUCK, RIDE SAFE

 

wow. you guys are so full of useful info. thanks. and my vin is not showing a recall. which totally sucks. I need to just take it to them then right?

 

Sounds like a stator going bad, it will eventually leave you stranded. If you charge the battery, you will be fine for short trips.

The real risk is continuing to ride with a stator going bad, will also fry the Voltage Regulator.

 

alright i'm back on this subject. I haven't rode any in the past couple months due to it being cold 2 months ago, and 1 month ago I injured my back. but today I did all the testing with a voltage meter. I have the manual to assist me. Here is what I found.

Battery standing charge was 12.5. Upon crank it didn't go under 10.2.
Once started it went to 14.2 with some throttle, then as was the case while riding it, the battery light and engine light came on and the voltage dropped to 11.2-11.5.

Next I checked the stator ohms with the multimeter leads in both connectors it came to .2-.4 ohms. Then I checked the stator to ground and it read 0.L. I'm not sure if that was what it was suppose to be or not. I think the book said no continuity but others were saying the mulimeter would say 1.L?
After that I connected the leads the stator output and turned the multimeter to AC. Cranked the engine and it read 38-52 volts. (what the book said it should)

Then, even though it doesn't say it in the book, nor does it say to test the voltage from the voltage regulator; I attached leads to the pos and neg. from the voltage regulator and cranked the bike. should have been DC current right? it read .23-.27. Output from there is supposed to be 14.3-14.7.

So, after this long a$$ post, the question is; I need a new regulator right?

 

Did you also test the lead coming from the stator?

 

couldn't have done any of that today without the multimeter. Seems like you didn't even read my post.

 

Ah, sorry bud, I misread the stator part as you testing the regulator. Though it was strange testing the resistance there. At any rate, if the voltage coming from regulator is that low that would be the prime suspect. What you read from the stator seems to be what it should be. 0.L stands for 'overload' or 'open loop' (depending on who you talk to) and means it is not grounded (which is good). I'd get a new regulator, then without installing it on the bike plug it in and test it. That way if it isn't the regulator you can still return it.

Edit:
The reason that part of the comment was in quotes was because it was a copy/paste from a different thread on the same issue. The bulb part was in reference to someone's test not using a multimeter:

What RPM was the bike at when you were reading 38-52 volts? The reason I ask is because I had similar symptoms with my bike and thought it was the regulator but it turned out being the stator. That's why I suggested not installing the regulator and testing it by just plugging it in before installing...

 

no harm, I don't have a RPM gauge on my bike. I just turned the throttle a little past idle. I have a 2012 Nightster still under warranty. I was wanting to make sure I knew what the problem is before I schedule an appointment with a dealership that is over 110 miles from home. I'll probably have to tow it there or ride it till it dies and then call a tow.

 

Ah, okay. Then just past idle those voltages are within acceptable range. If it's under warranty just tell them it's the stator or regulator. Let them know the voltage at the battery is way too low when the bike is on and they'll take it from there. Even if you told them the tests you did they'll probably redo them anyway.

 

I wanted to update this just incase anyone was following this thread. I replaced the Voltage regulator with one from cycle electric on may 1st. Since then I've put over 400 miles on my bike and have had no problems since. The battery light and check engine light have not come on again at all.

Thank you everyone that provided input. I am really appreciative.