I have an 87 1100XL and I'm not getting the correct charging voltage when I rev it up. I've checked the stator for a ground and for shorts, everything checks out OK. The manual says that it's the regulator. OK, I replaced that. Still when I check the voltage at the battery I only get 12.95 volts across the terminals.... I should be getting 13 or more.......I'm stumped....am I checking the charging system wrong?

 

12.95 is as close to 13 as it needs to be.

What *exact* RPM are you checking it at?

Are you checking the STATOR? That should be a lot higher.

 

With the bike off, you should get a volt reading (at the battery) of about 12.9 volts. A 12.7 volt reading is approx. a 1/4 discharged battery! With the bike running you should get approx a 14.3 to a 14.5 volt reading. That is a proper charging rate.
It is in fact that simple!
Under a load (lights on or controled short with a load tester), with the bike off, the battery should be able to maintain approx. 12.9 volts. If the volts drop off to fast the battery needs replacing. The first test to check the battery is always to make sure it is fully charged and then load test it.

 

I don't see that you checked the OUTPUT of the stator. It should be between ~20 - 70 VAC with the bike running. The higher the RPM the higher the voltage.

 

The output was 22-23 acv

 

Even when you rev it up? ...stays at ~23 volts? ....if so it is time for a new stator.

 

It goes above 22vac when revved up.I wasn't paying any attention on how high it was going just that it was within specs according to the tech manual. I spoke to my son who has an 85 sportster and he had the same problem and he replaced the battery.......Dad, "replace the battery"! Did I mention this is the son that went to a Technical college for auto mechanics with an Associate degree and majored in electrical diagnostics.........we will see if my money was well spent on his education!

 

Yes, It's charging again!!!!! The son was correct....changed the battery and it's charging perfectly(13.88 vdc). I guess my money was well spent on the sons education! Thanks for all the help