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midwilshire
Oct 23rd, 2006, 9:59 pm
Assume I have a friend who let some electrical things on his LT run for two weeks without realizing it. Assume further that the gel battery is stone dead.

My friend plugged in the BMW gel battery charger and left it on for 3 days straight -- no noticeable difference. Dead.

Does he need a new battery, or can he jump start it and ride around for a few hours and be like new?

cfell
Oct 23rd, 2006, 10:09 pm
Seems your "friend" need a new battery. There are some chargers which will not charge unless there is "minimal" voltage present. I don't know how you will get your friend's battery to that level...

dcwchfc
Oct 24th, 2006, 4:47 am
I left the bike sit for about 3 months, turned the key, and nothing at all lit up.
I put a gel charger on it for about 12 hrs, got a glow from the dash. Then I put a 6 amp charger on it for another 12 hrs, lit up brightly. Attempted to start it with the charger attached. It fired right up. Then I turned it off, removed the charger, started right up again. So I put the gel charger back on it, and in about 6 hrs, the green light on the charger glows steady, showing a full charge. Worth a try

messenger13
Oct 24th, 2006, 6:07 am
I did the exact same thing. But before running out and buying a new battery, I threw it on my 2A/10A/50A car charger for a day. I set it on the 2A setting...but every once-in-awhile I'd give it a 10A jolt for a few minutes. The battery came back to life and was fine afterward.

DaveDragon
Oct 24th, 2006, 6:57 am
Check this out: http://davedragon.blogspot.com/2006/10/franken-battery-or-resurrecting-dead-on.html

messenger13
Oct 24th, 2006, 7:08 am
Check this out: http://davedragon.blogspot.com/2006/10/franken-battery-or-resurrecting-dead-on.html

My new mousepad...

http://images.cafepress.com/product/23930175_240x240_Front.jpg :rotf: :histerica

DaveDragon
Oct 24th, 2006, 7:19 am
My new mousepad...

http://images.cafepress.com/product/23930175_240x240_Front.jpg :rotf: :histerica

So far my traffic proves your right! LOL!

But still, The technique I used works well.

cfell
Oct 24th, 2006, 9:58 am
I agree you can Franken-rect batteries occassionally, but there is no promise the battery won't just croak someday...

Of course, my battery, only 2 years old on the NEW '05 just up and quit in the middle of nowhere (Cedar Park, Texas)..

Ok, not quite "nowhere", but it's next door when the BMW shop is 40-50 minutes away and you are about to head off on a weekend trip... Bike batteries are still a krapshoot.

BLBantz
Oct 24th, 2006, 10:04 am
Your friend should leave his gel charger on the battery whenever he is not riding.

strsout
Oct 24th, 2006, 10:10 am
Tell your 'friend' to try charging it with a car charger, about 10A for couple hours, then goes back to the low Amp charger.
I had the same problem, see:
http://www.bmwlt.com/forums/showthread.php?t=7291&highlight=battery
I did it and my now 4 years old battery revive and still running perfect until now.
Worth a try.

midwilshire
Oct 24th, 2006, 10:21 am
I told my wife last night, "well, I don't if know that battery is reparable, but I posted on the LT forum, so we'll have an answer in about 10 hours."

Never fails.

HammerStar
Oct 24th, 2006, 4:12 pm
Hello;

Had the problem of a dead battery on a '05 this summer and will throw out my "repair" method for discussion. I plugged in the battery tender to the accessory plug but showed no charge light as others have found, at that point I used jumper cables from the bike battery to my car as though to jump start. As soon as I had made the connection the charge light showed on the battery tender, so I removed the jumpers and the charge light stayed on. I left the battery charger plugged into the bike and it took about three days to bring the battery up to a "green light" full charge condition at the 900 ma charge rate of the tender - no battery issues to this point.....................


Steve Collier
'05 KLT

Dick
Oct 24th, 2006, 7:55 pm
Good post, Steve; that sequence of events is Ed Zachery what the Battery Tender Plus instruction manual sez to perform if your battery is deader'n a door knob. That Tender has to see at least 3 volts minimum in order to be activated and start doing it's job. Manual sez you gotta 'fool' the Tender's circuitry by momentarily jumping the dead battery to a known good battery.

I've never had to do that procedure, butt have talked with several folks who have and it's a definite remedy that should be performed prior to scrapping the battery for a new one - all other thangs considered (age, etc.).

Hello;

Had the problem of a dead battery on a '05 this summer and will throw out my "repair" method for discussion. I plugged in the battery tender to the accessory plug but showed no charge light as others have found, at that point I used jumper cables from the bike battery to my car as though to jump start. As soon as I had made the connection the charge light showed on the battery tender, so I removed the jumpers and the charge light stayed on. I left the battery charger plugged into the bike and it took about three days to bring the battery up to a "green light" full charge condition at the 900 ma charge rate of the tender - no battery issues to this point.....................


Steve Collier
'05 KLT

toronto
Nov 21st, 2006, 7:10 pm
....the evolved gas from using a car charger or boost? I suppose a boost wouldn't do much, but generally when I charge a car battery, which is also lead/acid, I take the plugs out as gas is evolved from the charging process. Where does this go if I use a car charger on the dead battery as I can't figure out anyway to open the battery.

(I've got exactly the same issue as all the previous posts - dead and the trickle charger made by BMW won't "kick in" even after several days)

Rod.

Dick
Nov 21st, 2006, 7:32 pm
....the evolved gas from using a car charger or boost? I suppose a boost wouldn't do much, but generally when I charge a car battery, which is also lead/acid, I take the plugs out as gas is evolved from the charging process. Where does this go if I use a car charger on the dead battery as I can't figure out anyway to open the battery.

(I've got exactly the same issue as all the previous posts - dead and the trickle charger made by BMW won't "kick in" even after several days)

Rod.
Rod - did you have an opportunity to try 'hammerstar's method of tricking the BMW battery charger into seeing at least 3v at your 'dead' battery. His method is in his post earlier in this thread:

Had the problem of a dead battery on a '05 this summer and will throw out my "repair" method for discussion. I plugged in the battery tender to the accessory plug but showed no charge light as others have found, at that point I used jumper cables from the bike battery to my car as though to jump start. As soon as I had made the connection the charge light showed on the battery tender, so I removed the jumpers and the charge light stayed on. I left the battery charger plugged into the bike and it took about three days to bring the battery up to a "green light" full charge condition at the 900 ma charge rate of the tender - no battery issues to this point.....................

Just wonderin' if that procedure worked for you? I don't think there should be any worry about off-gassing since the duration of hook-up to the good 12v battery is so shortlived. YMMV.

cfell
Nov 21st, 2006, 7:50 pm
Rod,
Does your battery have "caps"? I haven't seen a gell cell that has them.

When I used the other kinds, I removed the caps to check the levels. But i would put them back on and use the "vent" line.. that will fulfill that gas venting function.

Do you have a "gell cell" , if so, no need to be concerned about "venting".

I suggest you get a voltmeter ... you will need one in the future.. Then check battery voltage. If you don't have at least 3 volts, the charger won't "kick in".

If you have no voltage, it is possible you have an internal 'short' in the battery that breaks the circuit. If that's the case, you can't "fix" it, must replace it.

You can bring the battery to your local BMW shop and they will check and attempt to charge for you if you don't feel comfortable following the steps.

toronto
Nov 22nd, 2006, 9:16 pm
.........thanks for all the info. I've taken the battery, charged it off the bike for a day, and now I get over 11 V across the poles. Put it back on the bike, and the lights go on but not enough juice to start it. So, plugged the BMW charger into the socket on the bike and red light lit. Leaving the BMW charger on now.

So, now, the big question is, do I have enough power in the battery so it will "start" to charge on the BMW charger - any experience with this. Does this sound promising to anyone? It seems, from the threads above, that this might work.

I guess I'll check tomorrow..........

Rod.

toronto
Nov 26th, 2006, 5:15 pm
.......and I'm off and riding. Thanks to all, guys.

Much appreciated.

Rod.

UncleRock
Nov 26th, 2006, 6:21 pm
Do gel batteries have caps and cells.
This is a trick we used to use, take 3 regular asprin cut them in half, crush up one half for each cell, top up with water. put on charger.
I sure someone on here can explain why that works, :cool: I'm even more sure it ain't me! :eek:
Just like the asprin making acid in your belly
Rock