Riddle me this batman. 2008 FLHTPi, working police motor quit charging Sunday to the point that I rode it until it completely died trying to get it to the shop without a tow, just made it and only had to push it a 100 yards. The wrench checked it out today after charging the battery and says it is putting out 14 plus volts. I am thinking something is opening up in the voltage regulator when it is hot. Anyone dealt with a similar issue that can shed some light. Driving a Tahoe sucks compared to my motor.

 

Original battery? How many miles on the bike? Sounds like you are on the right track. I suspect the voltage regulator.

 

40,000 on the bike has had one stator and voltage regulator in the past. Battery is about 6 months old.

 

Get the bike good and hot, and check the regulator.

 

Make sure the regulator wire is properly connected, its underneath the regulator. My bike when it was new did the same thing, would charge sometimes, but other times not. Turned out to be a poor connection was all it was.

 

Open the primary and smell for burnt electronics.... that awfull rotten egg smell. If it smells like oil its all good. Double check the battery is putting out 12.4v or so . Should read 14.v or so idling or at 2 grand a little more. If that's good REPLACE the voltage regulator. Just did this two weeks ago. Cost me $217 at the dealer for the part.I had no choice as I was leaving on a motorcycle trip the next morning. Charging system has been great ever since.

 

The first thing I checked prior to heading to the shop.

 

When the wrench got back to the bike to adjust the clutch he said it wasn't charging again.

He tore into the primary and said he only smelled burnt clutch, which is pretty common on a cop motor. All of the stator windings look good, not burnt and showing the proper resistance. He said the rotor came off too easy so he is replacing it also as he believes the magnets are not as strong as they should be, but most likely not causing the problem.

While in the primary he discovered wear on the compensator and a broken spring in the compensator spring pack, so all those parts are being replaced now. He does a great job of keeping my ride in good shape.

 

Final Update: After the repairs the bike was charging but right at 14 volts rather than 14+ like usual and it would drop with load quite a bit 12.5 such as stopping at a stop light and keeping your foot on the brake.

It turns out that the issue was in the DC cable coming out of the voltage regulator. The wrench said the cable felt hard/brittle near the plug. He did not dissect the cable to see what exactly it was but replacing the cable has it back to 100% now.

 

For advice on checking your charging system read the Stickies in The DIY Electrical section. You'll need a multimeter. As suggested by larsfum, check when good and hot as well as when cold. Cleaning connectors and grounds is good therapy and may just help improve things!