Gents,
I have an 03 Lowrider with a charging issue that just reared up again. 3 years back I replaced rotor/stator, rec/reg and battery to restore charging voltage.
The rotor had one grenaded magnet. Since all other components were original, I decided to replace the rest as a matter of course.

The bike has a bored and stroked 120" Zippers built engine and recently began breaking down (missing) under hard throttle. An inspection
of battery voltage of ~ 12.4vdc with bike running. Battery voltage was dropping below 9vdc while cranking so replaced with 20ah 310 CCA AGM battery to assure
I had a healthy battery. Now cranking voltage doesn't drop below 10.2 vdc but charging voltage is still "0".
Stator to ground test passed with no short to ground or resistance between either field lead and a chassis ground.

With engine off, separated the rec/reg input plug from stator output and started bike. Read ~16-20Vac/1000 rpm with a starting reading of 18 @ 1000 up to 58Vac @ 3000
so plenty of source voltage.

Static diode test of rectifier passed with .5 ohm readings on Fluke DVM from red to rectifier ground lead and black to either AC input lead.
and infinite resistance reversing the leads.

Ground continuity checked good from chassis/engine back to battery

Decided to replace the rect/reg with new part. Just installed it and have the exact same results- no charge voltage.
This isn't rocket science and simple logic led me to think the regulator could've still been bad
with everything hooked up. Stator still putting out almost 20 Vac per 1000 rpm.

Any ideas? The only thing that hasn't been replaced is the stator/rotor and all seems good on that end...

 

Maybe a stupid question, but, have you checked the fuses?

 

Did you ground the REC/REG? There is a small wire with an eye on it, wouldn't hurt to scrape the paint on the ground connection. On my 02 FXD the charge at idle is around 12.4V and above 2200 rpms it's at about 14.4v. Single phase alt. is pretty anemic. As far as parts, I trust Cycle Electric before HD.

 

Good question. Yes I'm getting battery voltage across the bus fuse that ties the charging wire to the battery and its a continuous wire (no spicing) from regulator to fuse post.

 

Thanks for the reply John.; Yes,I made sure I had a good ground from the REC/REG ground wire to chassis and even ran a temp wire back to battery ground for giggles. The new regulator is from USA-1 through Ebay. The diode tests pass on both old and new REC/REGs. I agree that alternator output on these models isn't stellar but I remember 13+ vdc at idle after the last system overhaul a few years back. Would like to set up a bench test for REC/REG if possible. I can get hold of a single phase 500w VariAC and have a good spare battery. Do you see any flaws in that kind of setup?
Just running out of options and don't want to continue blindly throwing $$$ into the wind

Mike

 

You checked continuity of ground, but how about the positive leads and connector integrity?

 

Not to beat a dead horse, but how are you measuring this? If you put the meter across the two sides of the fuse and see battery voltage, it means the fuse is blown. If it's good you should see zero volts. (Zero doesn't definitively mean it's good, but anything else means it's bad.)

If you read voltage from the fuse to ground you will see (exactly) the same reading on both sides if the fuse is good.

 

Compufire 3 phase charging system! Installed at 53,000 miles and still going strong at 165,000 miles on my 2000 S/E Road Glide 10 years later. The '00 to '06 charging systems from HD were junk.(3 stock units were installed by the time I hit 53,000 miles!)