Hello everyone, did lots of searching but didn't come across much that is too similar. I ride a 2009 FXDF with about 25k miles, it has a Bassani RR Mega Power exhaust and Arlen Ness Big Sucker breather modified to vent externally. It has been mine for the past couple of years or so, about 10k miles. I have made no recent changes to the bike other than replace my exhaust bracket and spark plugs a couple of weeks ago. On to the problem...

About a week and a half ago, I went to start my bike up to ride to work and all I got was the dreaded clicking of a dead battery. Got it plugged into the battery tender before I left, and the tender indicated a full charge. I've had it plugged to the tender most of the time I haven't been riding since then, with no problems on my normal rides.

Then on Friday, I unplugged it from the tender and rode it 4 miles to my job with no issues. Then when I was riding it home after my shift, my check engine light came on and my bike was idling at about 2,200 RPM according to my Dakota Digital gauge. The high idle and CEL were intermittent during the ride. I toggled to the Voltmeter on my gauge, and it indicated that when the bike is running anywhere over 2,000 RPM or so that it is at 18.2 volts. I have read that the gauge isn't as accurate as using a voltmeter, but I don't have a voltmeter available to check it immediately and it can't be THAT off.

Does anyone have any idea of what my problem might be? My first guess would be voltage regulator, but could a bad battery have wrecked my voltage regulator and be causing these problems? I'm going to try and borrow a voltmeter from a friend, but in the meantime hopefully someone can help me come up with some ideas. I need to get this thing running properly so I can get my car to a body shop to get repairs done by damage from a hit and run, but don't want to be left without transportation (and I'd rather ride the bike anyway).

 

Sounds like a regulator. Check connections, grounds, battery terminals etc for tightness, cleanliness and integrity. Usually they fail when hot. If possible, try to heat the regulator up and see if you can recreate the problem.

There are numerous good posts and online resources for checking stators and regulators.

A regulator charging that high will damage your battery.

 

Edit to delete double post

 

Thanks for the reply. Forgot to mention, I checked terminals and ground and took it for a spin, and the problem happened again. Definitely wouldn't have been caused from being hot though, it was a cool night and the bike had only been running for about 3 minutes before I had the problem. After checking the battery with a volt meter, turns out the Dakota digital speedometer one is almost dead accurate and the battery is still reading at 12.7 and I don't believe it was getting too low when cranking over.

I'm gonna check the regulator wiring after work and then probably order a new one. Does anyone know if the regulator has its own ground to the frame?
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