2006 Road Glide
This is really pissing me off, again.
I had a small oil leak coming from the oil cooler adapter for the past few weeks. Finally got around to fixing it. Had to remove the oil cooler and regulator to get at the problem. Put it all back together and took it out for a ride. Got a few miles down the highway and noticed the voltmeter was fluctuating from a little over 14 down to about 10.
Last round of electrics turned out to be a chaffed cable harness from the regulator to the battery.
Recently installed a new voltmeter because the last one didn't drop to 0 when the bike was turned off.

 

Bad connection where the regulator plugs into the front of the motor to get voltage from the alternator, maybe?

 

If the alternator connection was intermittent, the voltage would only drop to the battery output which is about 12 - 13VDC. This drop below that indicates something is shorting out, i.e. direct battery to ground short.

 

I had a similar symptom. Turns out that the wires from the alternator go forward across the frame member that supports the front motor mount and on my bike I discovered that they were chafed in that spot also.

 

Yep, been there, done that one too.

 

Try hooking a volt meter directly to the battery with bike running. See if the meter and the bike's voltage gauge match. The Harley volt meters are buffered, (needle movement is slowed). If the volt meter is steady and above 13 to 13.5 at idle start pulling on the wires going to and from the voltage regulator. Follow the wiring harness along the frame paying particular attention to the areas where the harness is ty-wraped to the frame. You may find a chafed wire. A bad connection at the plug under the regulator or a poor ground connection at the regulator mount.

Good luck, intermittent electrical gremlins can be a bitch.

 

That's pretty much what I had in mind to do, starting this afternoon. I didn't throw that many things around the garage yesterday when I got the bike back home from the test ride.
The fluctuations up and down were pretty quick as though it were an intermittent short.

 

Tested the regulator tonight. Tested the output of the stator, it was good on all three legs. None of the legs were grounded to the bike though, which is good. Applied the Stater input to the regulator and started the bike. No output on the battery side of the regulator. I measured right at the regulator. I checked the other regulator that I had on the shelf and it didn't have any output at the DC output either.
I'm really not sure what the hell to think now.

 

I'm a hack at electrics anyway but if there's no output on the battery side, isn't that indicating a bad regulator?

 

I would think so, but the more important question is: why are these regulators burning up?