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Discussion Starter · #21 ·
I'm confused. If it shows 12.8 with the scooter running, its a charging system issue. It can't show 12.8 and 14.ish at the same time.

Charge the battery with one of the cables disconnected. Not with a little ,2 amp charger, but a real battery charger. It should read 14.6v after more than 20 minutes at 10-15 amps. That fist little voltage bump is a surface charge. Then after it sits for 12 hours off the charger and disconnected from the scooter, it should still be 12.6 or a little more. Now load test it at its rated amps. That little hand held thing you see people use will not test it at the rated amps. They top out at 50 or 100 amps. If it passes that, the battery is good. Charge it back up and reconnect the cable.

The charging system is easy. No grounds on any of the stator leads. ZERO. Then spec voltage between any two of the stator leads at the prescribed rpm as per the factory specs. That's Harley specs, not something some third party says it should be. Inspect both sides of the plug while its split. The regulator needs a good ground, so that means the fram needs a good ground. Don't trust an ohm meter, voltage drop it. Then inspect the positive circuit from the regulator to the battery. No repairs, or splices should be trusted. And the eyelet at the battery should be soldered. The regulator runs its own show. If there is AC currant from the stator, it rectifies it to 12 volts with diodes, then feeds enough DC current to the battery to maintain 14.5 or there bouts. Any extra current is shunted to ground. So usually, any funky work one day not the next stuff is rooted in the regulator. Any current flow with the motor off, on the lead to the battery, is a bad regulator.

One other thing I see on those old scooter a lot is they are missing the shunt between the battery and the relay where the wire from the regulator is attached, Not sure about that particular scooter, but on a 94 Ultra the wire from the regulator attaches to the main relay on the negative post. There is also a red wire on that post. The positive post (copper) has a black wire that attaches to the positive battery cable at the starter. And there is a lot that can go wrong there. So for diagnostics, just connect that regulator wire to the positive battery post.
Not running at 12.8, that was sitting off voltage.

I'll read through your reply tomorrow and check through the system again.
 

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So I bought a 1995 FLHR road king about 2 months ago. I have a lot of work and moo-la into this project.
-new battery #1 (brand new Die hard TX24HL)
I thought I had all of the kinks figured out and took the bike on a long road trip! Went great until about 1200 miles in when the bike started acting like it was running out of gas and died on the side of the road (with a completely dead battery) not low, fried. Like it started great multiple times that day and it just went kaput while driving down the road...
BATTERY#2 (warranty replace tx24hl)
LONG story short and a tow home, I put a brand new battery in and the beast was like a new bike again for about 2 weeks when it did the same thing.

Battery #3 (another warranty replace tx24hl)
And I'm checking all the components again.

-Stator is cycle electric 32amp and installed 2000 miles before I bought the bike. Not grounding and 35-40 AC volts at 2k rpm (Tests good)

- regulator is brand new (custom chrome brand) 13.2volts while idle, 14.3V above 2k rpm. (Tests good)

I checked draw on the negative with the regulator was .8 mA and 28mV
When I remove the long wire from the regulator to the 50amp circuit breaker, the draw went to 0.0mV, so I figured the regulator may have gone bad?

Purchased a cycle electric regulator and the draw is actually worse. Now I'm getting 1.4mA and 80mV? I didn't start it to check charging cause now I'll assuming my old one was perfectly fine.

There must be something I'm missing.. why would I get an 80mV draw with ignition off from a new regulator that goes to 0.0 when I remove it from the system?

Why am I burning up batteries? Is "die hard" battery just a bad quality battery that can't handle being in a harley?

If you might have any suggestions, let me know please, I'm bald now from pulling out all of my hair.
Just a FYI, i went through three batteries before I figured out it was my TRICKLE charger frying the battery at night. New battery, new charger, no more fried batteries.
 

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I had a similar experience to Ptumblety, I lost a battery each, on two older bikes, to Battery Tenders. I now use a battery tender very sparingly, once a month in the winter, and once in spring when it's time to come out of hibernation. Since then I've required zero new batteries. Regards, and good luck diagnosing your' problem.
 
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