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Dead Battery or Fried Alternator on my '95 K1100LT?

chrisabraham

New member
Last week, I ran by new battery out by forgetting my key in the bike, lights and everything else on. Tried to roll start her. Nope. Trickle charged at deep cycle, 2AMP, and no real take in the time I had.

Tried to jump using the trickle charger when I ran out of time using the 55AMP jump setting. No go, but regretted doing it.

It's not nothing, it's the grunt of a starter. A lame grunt. Afraid I fried something using the jump mode.

Next day, trickled it on 2A normal and it got some charge.

Called Khanh Nguyen at EUBMW for some help. He's a new dad! A 2nd boy! Mazel tov! He said I didn't do anything wrong and an overnight at 2AMP trickle should make it all right.

The building manager told me I needed to move the bike. Folks pushed me and I got started. Rode 80MPH+ around 495 for around 45 minutes (Columbia Pike to 395S to 495 inner loop to GW Parkway, got hope, parked, tried starting her.

Same lame starter grind, it feels like she didn't take any charge.

Wondering if I fried anything (I didn't jump with a car) or if the battery is shot or if I did something else stupid.

In the perfect world, I would just need a new battery (even though this one is only months old).

Any advice? Any insight?

Thanks in advance! :hungover:banghead:dance:scratch
 
Chris,

It's just about impossible to diagnose electrical faults if the battery's toast. Even though near new, it may be bad. The most definitive assessment is a load test, which can be done at an automobile electric shop, many auto parts stores, or even on your own with the right equipment. Many folks just punt and buy a new battery. Before I did that, 'tho, I'd disconnect, clean, and reconnect all the battery and ground cables; with age, connections degrade and may look OK but not tolerate the current flow that's needed for correct operation.

With a known good battery installed, you'll be able to see if the starting system operates correctly.

With the starting system operating and the engine running, you'll be able to see if the charging system operates correctly. If it isn't charging, or is charging poorly, remember that the alternators on these bikes are auto types; the brushes and regulator can be changed, and any generator shop can rebuild them.
 
Unless you accidentally reversed the polarity on any of your attempts, the previous post is bang on. Can't do much without a known good battery.

Batteries do just give up without warning.
 
Mahalo (Thank You)

Thank you so much, friends. I appreciate your deep help with all the shallow info I could supply.
 
She started up right away this morning. Rode down to EUBMW anyway. Khanh checked and the battery is at 60%. Will replace it and get an oil change in a couple weeks. Weird. I'm grateful though. Replaced my brake light. All's well.
y4uvahyg.jpg
 
When you deeply discharge a battery it often damages the battery. How badly damaged depends on the type of battery - wet cell, absorbed glass mat, gel type etc. It also depends on the actual construction of the battery. Sometimes it seems just like dumb luck. I have run batteries down and had them seemingly recover. I have run batteries down that never again took a full charge. I think you have one of the latter.
 
Went through the same thing earlier in the week. I had come home from work, and was in a hurry to catch the plane for my 10-day vacation. I didn't notice that I left the key on. Upon returning from vacation I discovered by error, and the battery had 0 volts. Hooking up a "Smart" battery charger will usually come back and say that the battery is damaged or there is an open short. In this particular situation, the "smart" battery charger will NOT charge the battery. This can lead you to believe that the battery needs to be replaced.

What you have to do is use jumper cables with a good battery to get the drained battery partially charged. Once the drained battery has a partial charge, you can then hook up a "smart" battery charger. The "smart" battery charger will then charge the partially charged battery. It will then take about 48 hours to fully charge. While "smart" battery chargers can help you with battery problems, they fail in this particular situation.
 
Went through the same thing earlier in the week. I had come home from work, and was in a hurry to catch the plane for my 10-day vacation. I didn't notice that I left the key on. Upon returning from vacation I discovered by error, and the battery had 0 volts. Hooking up a "Smart" battery charger will usually come back and say that the battery is damaged or there is an open short. In this particular situation, the "smart" battery charger will NOT charge the battery. This can lead you to believe that the battery needs to be replaced.

What you have to do is use jumper cables with a good battery to get the drained battery partially charged. Once the drained battery has a partial charge, you can then hook up a "smart" battery charger. The "smart" battery charger will then charge the partially charged battery. It will then take about 48 hours to fully charge. While "smart" battery chargers can help you with battery problems, they fail in this particular situation.

Agreed. Which is one reason I still own and occasionally use a dumb 1.5 amp trickle charger. But, totally discharging a battery, even just one time, can ruin a battery. It might not, but it very well might.
 
You're probably right. We'll see. Maybe it'll fully recover.

Any advice on solar panel battery conditioners?

Good ones work OK for maintenance charging. The problem is how to know a good one when you see it.

The output should be regulated so as to not overcharge and damage the battery. And the output should be diode equipped so the panel doesn't discharge the battery over night.
 
Any advice? Any insight?

Did you measure the battery voltage while it was being charged and while the engine was running? That is a start.

Since you asked, I would not bother with a solar panel battery conditioner. Just charge the battery and monitor its voltage. Then see how it retains that charge a day after you disconnected the charger. Of course voltage alone is not a true indication of a healthy battery.
 
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