Is it my battery? 2002 ABS ST1100A

[ArTravlR]

Symptoms: On a recent ride the ABS lights kicked on the dash when the cooling fan started in stop-&-go traffic. After a head scratch/reset we made it home a few hundred miles no issue.
Last weekend she started right up and after a couple minutes, she died. A restart had the battery as weak, clickity click. Three year old YUASA. Pocket battery jump start and the ST cranked right up but dies after disconnecting the jumper battery. I feel like it's the battery and am disappointed in it's performance. Any recommendations? BTW: Any reason this could be a symptom of a failing alternator or other electrical issue? TIA

 

[Smudgemo]

Probably the battery, they don't last all that long. Have an auto parts store do a load test on the battery if you want, although my last one they said was good and it wasn't.
Make sure the connectors are clean and tight, check the voltage when it's running, the usual stuff. Hook up cables form a non-running car. to see if it acts normally. At least if it's the battery, it's your cheapest fix.

 

[kiltman]

Did you do an error code test? A weak battery would cause the ABS system to go wonky. I would check your battery terminals are tight. I would also check the connector to the main relay. I’ve had YUSA batteries last longer than three years on an ABS bike.
I doubt you would have alternator issues.

 

[Al st1100]

simple , cheap, volt meter would tell you if it's charging. Start it with the jump pack and before taking it off check the voltage. Should be above 12 more in the 13-14 volt range ( above idle speed). If it's low do as kiltman says. Just putting a new battery in will get you stuck on the road if it's not charging.

 

[jrp]

Don't take offense, but did you check to see if the battery connections are tight and clean?

 

[Ron]

Check the connections and water if it has water. The ABSII is sensitive to lower voltage situations. I don't recall anyone having trouble with the 40 amp alt. Most of my batteries last long enough that I don't recall their age. I do ride at least a little (25 miles) several times a week.

 

[Larry Fine]

Pocket battery jump start and the ST cranked right up but dies after disconnecting the jumper battery.

Well above idle, the alternator should be producing enough power to keep the engine running.

 

[ArTravlR]

Well above idle, the alternator should be producing enough power to keep the engine running.

Exactly why I posted the question. It should have kept running. The problem will have to wait until I get back down there in a couple days. Thanks everyone.

 

[mjc506]

I did have an issue on a little 250 honda where the battery terminal broke internally, completely open circuit. Even when jump started, the bike wouldn't continue to run, as there was now nothing to smooth the voltage from the alternator, upsetting the electrics. That was an FI bike, but there's plenty on the ST1100 that won't be too happy with raw alternator current.

Unlikely, but worth checking.

 

[mortenk]

Some batteries don't last long. My experience is that it's random and not tied to a specific brand etc. I had a $200 Lexus OEM battery die after 9 months, while a $60 Walmart battery last 5+ years...and vice versa.

 

[ArTravlR]

For clarity: I live in N Arkansas and my ST is in SE Arkansas, about 180 miles south of me at my mother's place. I've had the ST since new (9-11) and it has 167,xxx miles. I have done all of the maintenance except the belt; my mechanic friend did that for me. I go to Mom's too often to mow grass, bush hog etc. Large place, two barns, etc.

Anyway, it's not the battery although replaced. ABS code says Faulty Power Circuit (7 blinks, cleared and returned). After installing the new battery with no faults showing on the ABS dash, we went for a ride. Everything is fine for about 5 miles and when I turned to enter the interstate there was an ominous sound as gravel in a garbage disposal for a bit and the ABS started flashing. So, the battery (new one) gets drained when the ABS fault is triggered. Bike dies while riding (but will idle under the shed purring like a kitten). Good thing I carried the pocket battery with me. Almost drained it too. We beat feet for the shed. Did not hear the sound again but the ABS code flashed 7 again. I had to leave it there and return home. I "feel like" it's the alternator bearing.

 

[mjc506]

If a new fully charged battery goes from fine to not-fine within a ride, you have alternator issues

The ABS can't drain the battery in a working bike - the system is designed such that the alternator recharges the battery as it's used (that's what it's for) and while it's possible to drain quicker than the alt can supply for short periods, things will start to melt before the battery gets drained significantly!!

Your ABS error is a symptom of low battery voltage, not the cause.

If it runs fine sitting in the barn, it may be heat or vibration related - worth checking the various connections for heat damage etc. But a replacement alt could be in your future.

Definitely worth checking system voltage (across the battery) with a multimeter or similar. Less than 13.5V with a running engine is likely to indicate that the alternator isn't charging.

 

[ArTravlR]

I guess it’s the alternator. 13.5v leakage test check is ok. Regulated voltage is 12.7v at idle. Immediate drop in voltage as RPM is increased. How difficult is it to swap out the alternator? Amazon replacement is about $165. Should I look at something else first? Wish I had a bike lift. Going to have to pay someone to do it…

 

[Smudgemo]

You don't need a lift to do this job. Nice to have, sure. If you haven't studied up on the alternator swaps, be sure to do so before you decide you don't want to do the job. I haven't removed the swingarm when going through either of mine, but getting to that point isn't very hard.
All things being equal, I'd rather have the Honda alternator, but at least one member has reported success with the Chinese alternative, which I assume is what you're looking at.
I'm also wondering if this later model can be rebuilt. I haven't seen anyone report doing that, but worth looking at.

 

[Slydynbye]

You don't necessarily need the whole Alternator. There is a voltage regulator that sits at the rear of the assembly.
It is a common and inexpensive auto part. Let me look for that info. be back shortly.

Edit Here it is Denso 126000-1160

 

[Slydynbye]

Here is what it looks like off the Bike but, I think you might be able to replace it (The regulator) without removing the Alternator.
Granted you will probably need to remove the swing arm to reach it.
While you are in there take a look at the brushes, top of the last picture. Regulator on the bottom

 

[Slydynbye]

It also just occurred to me that you could have something wrong with the Red wire

 

[kiltman]

I have done the alternator swap with the Chinese knock off on my 97. Check eBay because I believe it’s $135. The alternator is a good one well built.
Now if you’re just changing out the VRR and brushes then I think you will only need to remove the fuel tank, to gain better access to the alternator. And possibly the swing arm ( I need to look that up too)
if replacing the alternator I suggest you also get a new driveline boot. There are some tools you will need to acquire or borrow. There is a special tool for removing the castle nut on the swing arm and a 17mm Allen key. You can get that combo on eBay that tool will also assist in getting the proper torque on the nut when reinstalling it. A torque wrench and the tools that one would need to remove the rear wheel and calliper. The job can easily be done in a day.
I have attached the two units the new and old side by side, my tools I used for the job and what it looked like with the alternator out

 

[CYYJ]

It also just occurred to me that you could have something wrong with the Red wire

@ArTravlR : YES! That is an excellent point, and certainly a higher probability than a failing alternator or voltage regulator. It's also a heck of a lot easier to investigate and/or rectify than replacing the alternator or battery.

Here's a couple of links to educate you about the "Red Wire" and how to bypass it. FYI this is a very well known problem on the ST 1100s - I had a red wire failure when I was on the road in Belgium, it cost me $505 to fix it: $500 for the taxis, hotel room, meals, etc. when the bike suddenly went stone-dead at the side of the road, and $5 for the parts needed to carry out the red wire bypass.

Total power loss

Red Wire Bypass Modification

Here's a link to a photo that shows what happens when the red wire degrades: Melted Red Wire

Michael

 

[ArTravlR]

Thank you all. No, it’s not an obvious red wire issue. Fuse covers had never been opened before today. Checked all fuses, it’s a faulty alternator according to my service manual troubleshooting guide. Wiring harness looks okay but I can’t see it all without a lift. Good videos on the alternator swap on Utube. I’m neck deep in another bike project at home now so this hits aback burner.