I have an "86 FLHTC.
Over the past few months I have suspected that there may be "issues" with my charging system, but nothing really gave me reason to be overly concerned....... that is, until today.

The volt meter on my fairing has been faily consistent in indicating 12 - 12.5 volts whilst cruising, (2500 - 3000 rpm) with all the lights on, including spots. And 14v with the lights off.

Today, the volt meter statred to read below 12 volts, so I switched off the spots, and all was well, then, the dial started to fluctuate rather quickly between 8 and 14v. Almost as tho a waire was breaking contact repeatedly.

Next, the radio, which was off, started to put out a loud, low static with the erratic voltages.

Here are my assumptions:

1. Bad regulator - $100 plus
2. Bad charging sytem, so upgrade to a 32amp system - $250 plus
3. Bad radio which is somehow screwing with everything - $450 plus
4. Some unknown gremlin - unknown $

Any input sure would be appreciated!

 

Have you heard any strange noises from the primary side? The magnets can bust loose from the flywheel. If not you most likely need a regulator. But be sure and check all the wires and make sure you don't have one wore through and grounding!

 

Thanks for the reply....

No strange noises, but good idea 'bout checking the wires, it sure seems to be acting that way.

 

I would go to the 32 amp system That involves changing the volt reg and the stator The rotor can be re used. This has a much better volt reg to stator plug

 

Go through the diagnostics in the manual and see where your problem is.

 

A voltage regulator is likely.&nbsp\\; I only buy genuine OEM regulators and only have to do that rarely.&nbsp\\; Hopefully your stator is still OK.

 

Had a chance to take a look today.
No obvious signs of a short.
Radio does want to turn itself off at random intervals, so I removed it today.
Checked the contacts on the plug going to the regulator, and cleaned them (were very oily and black)
Also opened them up again so they had a tight fit.

Took hte bike for a run, and the voltage stayed just under 13 volts even with full light load, however the guage still "jumps" around a randomly.

I think I will take the plunge and upgrade to the 32 amp system if and when my stimulus check ever arrives [:@]

 

Had the same with my '90 FLHTC a month ago, replaced the regulator for the fix.
&nbsp\\;
This is the 2nd replacement at 85K, the first was when it was under 10K and still vibrating away before the bumps got knocked off. (Run in, in other words)&nbsp\\; Then it was the two prong plug into the front of the engine that had vibrated out and was being held by the rubber sleeve allowing it to arc and corrode away the prongs on the plug.
&nbsp\\;
Best of luck.

 

No need to change your entire charging system. Really. Isolate the fault. Simplier than you think. All you need is a $12 multimeter.
&nbsp\\;
I was really confused several times over the years....so I wrote this to help others:
&nbsp\\;
&nbsp\\;http://www.harley-davidson-hangout.c...ng-system.html

 

Thanks for the ref "Kiwidave"

Here is the next chapter.

Went ount to the bike this morning, to go to work. Turned on the ignition, hit the starter and.....
a brief "chatter" from the starter, and the main breaker tripped. Gave it a few minutes, allowed it to reset and tried again. Same thing. Third time around, nothing.

Left it on a trickle charge, so I'll check it again in the morning, but now I am beginning to think the battery may be bad?

For the record, battery was new last July. It is a sealed MOCO battery. All switches are new, again they were replaced last July. Battery spent winter sucking juice from a "tender" so it "should" be OK.

Well, I'll have to track this one down from both directions.[sm=smiley23.gif]