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Replacement Battery for R1200RT

grw

BMWNUT
I inadvertently left a device plugged into an unswitched socket in my glove box (my USB power converter for an iPod) and ran the battery down on my R1200RT. It's so dead that my BMW charger comes up with an error condition and won't even try to charge it.

Any suggestions for replacements other than another stock battery? I can't find any battery application charts that list the 2006 R1200RT. I checked WestCo and Enersys' Odyssey.

My next step is to go pull the dead battery and head over to one of the local battery specialty shops to see if there is something better than the stock battery for around the same price (or maybe less). The list for the R1200RT battery is $120.
 
You'll need a charger with higher output to bring it back. None of the float chargers will even attempt to charge a dead battery.

If you are set on a new battery the Hawker (Odyssey) line has been highly recommended for previous generation RT's. I have one in my R. Not certain if they will apply to newer RT's but I would consider one.
Unfortunately, the cost is about the same as a BMW battery. Since you already have the charger you may just want to stay with that.
 
I also would try a higher output charger (6 or 10 amp) to try to revive it. You aren't going to hurt it as it is not good the way it is.
 
+1...

A suggestion - if you have an old manual 10A charger hanging around.. hook a 12V bulb (a brake light bulb is good.. something about 20-30W) in series with the charger and the battery. The bulb will work to help regulate the charge going to the battery a bit. With the battery discharged - the bulb will burn brightly, limiting current going to the battery. As the plates start to reform in the battery and the internal resistance drops - the bulb will get dimmer. You should be able to safely leave it connected like this overnight (removed from the bike and somewhere away from flames.)

In the morning if the bulb is dim - disconnect the charger and bulb and connect up your BMW automatic charger - see if it will now complete the charge cycle.

Chances are fairly good on reviving the battery - and if doesn't work - you haven't lost a thing.
 
The BMW battery is a good one, superior technology. Try to revive it. The type of charger is irrelevant, float or otherwise. The problem with the BMW charger is probably that it has a protection feature that impedes it so it won't charge into a very low voltage or no voltage. Some other chargers will have this same feature -- they need to see some voltage on the battery leads to get them going. This is inteneded to prevent them from charging if they are hooked up reverse polarity. Your best bet will be a really cheap charger, which probably won't have this protection feature. If one charger does not bring up the voltage, try another one! Hopefully you have a voltmeter that you can connect to the battery to confirm if the voltage is rising (ie. the charger is charging). Incidentally, if the battery is really severely discharged, as would happen if you left a load connected for a really long time, then the voltage on the battery will initially go high, because it's acting like an open circuit and not accepting a charge. Given time the voltage will drop, the charge rate will rise, and eventually it will be charged. If it has not been damaged too much by the deep cycling, there's a good chance you will have dodged the bullet!
 
+1...

A suggestion - if you have an old manual 10A charger hanging around.. hook a 12V bulb (a brake light bulb is good.. something about 20-30W) in series with the charger and the battery. The bulb will work to help regulate the charge going to the battery a bit. With the battery discharged - the bulb will burn brightly, limiting current going to the battery. As the plates start to reform in the battery and the internal resistance drops - the bulb will get dimmer. You should be able to safely leave it connected like this overnight (removed from the bike and somewhere away from flames.)

In the morning if the bulb is dim - disconnect the charger and bulb and connect up your BMW automatic charger - see if it will now complete the charge cycle.

Chances are fairly good on reviving the battery - and if doesn't work - you haven't lost a thing.

Good point (and to all of you who suggested reviving the battery). I'll give it a shot. The only reason I hesitated was because I didn't know if there was a hazard in attempting to revive it with a conventional charger.

I'll post my results here.

BTW there do not appear to be a lot of (maybe any?) 12V 19Ah batteries of this size on the market. My guess is that a 17 or 18Ah would be fine if it fits and if the positive terminal is on the right side.

-Gary
 
Dead Battery

I had the same problem, but I took the battery out and took it to my dealer who happily replaced it under warranty. I also have the R1200RT. I am sure it is still covered under warranty..Jim
 
Good point (and to all of you who suggested reviving the battery). I'll give it a shot. The only reason I hesitated was because I didn't know if there was a hazard in attempting to revive it with a conventional charger.

I'll post my results here.

BTW there do not appear to be a lot of (maybe any?) 12V 19Ah batteries of this size on the market. My guess is that a 17 or 18Ah would be fine if it fits and if the positive terminal is on the right side.

-Gary

OK - So good news!

I pulled out the ReallyOld(tm) Sears 10/2 Amp 12V car charger I've had for years. Left it turned onto the 10A setting overnight. The next day when I removed the clips I noted a spark at the battery terminal. Very good sign. Voltmeter dutifully registered something between 12 and 15 volts (its analog and I'm lazy).

I hooked up the BMW smart charger (the little gray one that wants to be wall mounted) and instead of going into error mode it came up in full charge mode showing the battery as discharged.

Hopefully by tomorrow I'll be back in business.

Thanks to everyone who had more faith than I did in the battery. If the bike starts and runs after this I've just dodged a $120 bullet (for now).

-Gary
 
Good deal. Glad it work out for you. Just keep a close eye on it.

Draining a battery completely can ultimately shorten its life.

Hopefully, you will get away without replacing it for a good while.
 
Glad your battery revived. Now if you want to find out if it's really any good (which means if it has good "capacity", which is measured in amp-hours) here's a way to test. Disable the ignition so the engine will not start. Sorry, I am not familiar enough to tell you how to do this on your bike -- just don't do it by unplugging the spark plug leads (becasue that will potentially destroy the ignition coils) unless you ground the leads carefully! Hook up a voltmeter to the battery. Crank the engine for 10 seconds. The voltage should stay above 10 volts for the duration of the cranking. If it does not, either your battery is discharged, or it has low capacity and is at the end of it's usefull life. If the capacity is diminished like this, you will soon go to start the engine one cold morning, and it will just collapse. This is a great method of testing the battery on any engine, not just motorcycles.
 
Test that battery

Glad your battery revived. Now if you want to find out if it's really any good (which means if it has good "capacity", which is measured in amp-hours) here's a way to test. Disable the ignition so the engine will not start. Sorry, I am not familiar enough to tell you how to do this on your bike -- just don't do it by unplugging the spark plug leads (becasue that will potentially destroy the ignition coils) unless you ground the leads carefully! Hook up a voltmeter to the battery. Crank the engine for 10 seconds. The voltage should stay above 10 volts for the duration of the cranking. If it does not, either your battery is discharged, or it has low capacity and is at the end of it's usefull life. If the capacity is diminished like this, you will soon go to start the engine one cold morning, and it will just collapse. This is a great method of testing the battery on any engine, not just motorcycles.
 
If the capacity is diminished like this, you will soon go to start the engine one cold morning, and it will just collapse.

That's what happened to mine. After my ride out to California to do a Russell Ride-in, I left all my electrics on after I pulled the bike back in the garage. Four days later I hear "honey, you left the voltmeter on on your bike". Hmm ... the voltmeter isn't switched on it's own circuit, that means .... Yup, voltmeter was showing a fraction of a volt (0.8V) across the battery when I discovered the problem.

I was able to get the battery recharged, and it will start the bike on warm days or from inside the warm garage, but leaving the bike out in the cold and she had significant problem starting. On the voltmeter she looks good, holds a good 13.2V or so before I go to crank, but she's low on cranking amps to get that cold motor to turn over.
 
OK - So good news!

I pulled out the ReallyOld(tm) Sears 10/2 Amp 12V car charger I've had for years. Left it turned onto the 10A setting overnight. The next day when I removed the clips I noted a spark at the battery terminal. Very good sign. Voltmeter dutifully registered something between 12 and 15 volts (its analog and I'm lazy).

I hooked up the BMW smart charger (the little gray one that wants to be wall mounted) and instead of going into error mode it came up in full charge mode showing the battery as discharged.

Hopefully by tomorrow I'll be back in business.

Thanks to everyone who had more faith than I did in the battery. If the bike starts and runs after this I've just dodged a $120 bullet (for now).

-Gary

Actually for a bunch-o-reasons I didn't get around to putting the battery back in the R12 until last weekend. The bike fired up after a few tries and seems fine. Rode out to Cascade Locks from Portland on Sunday with no problems. I did hook up the charger when I got back. Looks like the wrap-up on the dead battery is that with a little tinkering it could be brought back to life and put back into service. With my old open celled batteries this would have been game over. I guess my opinion of the new technology is improving!

-Gary
 
Same subject only different

Hello everyone,

Regarding the RT, I have an '06 and do have the BMW Charger that you use through the onboard socket however, can I use a Battery Tender hooked directly up to the battery while connected to the bike? I've gotten a lot of input on this suggesting that it is not a problem. I've had people tell me they've been doing it for years and have had no problem. Someone recently received an e-mail response from Deltran, the makers of the Battery Tender saying it is fine as long as it is hooked directly to the battery.

My problem is that paragraph in the manual stating that due to the CANBUS system, you cannot charge the battery while it is connected to the bike. You must use the BMW charger (which as I mentioned, I have) through the onboard socket. Using common sense, I see no reason why it wouldn't be fine. It's not sending anything into the bike that's not already being sent by the battery, right?

I just got an F800ST and would like to get the Battery Tender with the two leads but, as I said, I'd like to be absolutely, positively, without a doubt sure! :laugh

Anyway, I'm of the thinking that it is fine however, being the type of person I am, I am a bit paranoid.

Thanks!

Tom L.
 
My problem is that paragraph in the manual stating that due to the CANBUS system, you cannot charge the battery while it is connected to the bike. You must use the BMW charger (which as I mentioned, I have) through the onboard socket. Using common sense, I see no reason why it wouldn't be fine. It's not sending anything into the bike that's not already being sent by the battery, right?

My opinion is that this is a bit of butt covering by BMW. It's part of the "keep the message simple" philosophy that current manual writers seem to follow where it is easier to say "no" and "don't do that" than it is give real explanations.

A properly working battery charger will not harm your bike when connected directly to the battery. An improperly working charger, can do lots of damage to any bike. BMW is correct if they are saying that the only way to 100 percent guarantee that an improperly working battery charger with just the right failure mode won't damage your bike is to charge that battery outside of the bike. If you have zero tolerance for risk you'll do as they say.

I have a fused pigtail connected directly to the battery and plug my charger into that when needed. Since my charger works well there is no reason for me to worry. Oh, I suppose a lightning hit at exactly the wrong time and exactly the wrong place could cause damage through my charger. But we don't get much lightning around here.
 
Hello everyone,

Regarding the RT, I have an '06 and do have the BMW Charger that you use through the onboard socket however, can I use a Battery Tender hooked directly up to the battery while connected to the bike? I've gotten a lot of input on this suggesting that it is not a problem. I've had people tell me they've been doing it for years and have had no problem. Someone recently received an e-mail response from Deltran, the makers of the Battery Tender saying it is fine as long as it is hooked directly to the battery.

My problem is that paragraph in the manual stating that due to the CANBUS system, you cannot charge the battery while it is connected to the bike. You must use the BMW charger (which as I mentioned, I have) through the onboard socket. Using common sense, I see no reason why it wouldn't be fine. It's not sending anything into the bike that's not already being sent by the battery, right?

I just got an F800ST and would like to get the Battery Tender with the two leads but, as I said, I'd like to be absolutely, positively, without a doubt sure! :laugh

Anyway, I'm of the thinking that it is fine however, being the type of person I am, I am a bit paranoid.

Thanks!

Tom L.
I direct-wired an upgraded rear socket on my R12RT to the battery (the front socket has been replaced by the plug for my J&M headset). I use this socket with any of the three battery tenders in my garage.

I believe there two reasons for the BMW "no-no" warning: One is a bit of CYA -- BMW doesn't have the time or resources to verify that every charger out there will work without damaging the bike's electronics, so they leave it at "ours works.' The other is what I'd call "true" -- the ZFE cuts off the sockets after a predetermined time if it does not receive a required signal from whatever is attached saying "keep this port open." The BMW charger provides this "stay alive" signal; other chargers don't, so it is fact that other chargers can't be used to charge the battery through the factory sockets -- at least as they are wired from the factory.
 
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Battery Died

On my 2009 RT I began to notice some deficiency in the battery while turning over. Bike ran fine once started and all systems functioned normally. While enroute to Duluth from Lower Michigan a few days ago the battery went completely dead. My Beemer dealer stated there have been some issues with new batteries in 09....I was stuck and ended up fitting a Yuasa YTX20HL-BS. The Honda dealer stated it was a 20 amp/hr battery, but the Yuasa site stated it was 18. Terminals were in the right posistions and all mounted without a hitch. The clamp purchase on the battery was improved using a rubber strap. It started the mount immediately in 25 degrees encountered a couple mornings. And it is lead acid instead of the gel crap...I share with other Beemer riders that Westco and the whole gel technology is the perfect solution to a non-existent problem......I had shorter battery life on my K-bike using Westco.
 
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Restoring Completely dead AGM battery

Often these batteries won't recharge once they are completely discharged. Here how to charge the dead AGM battery, if you have any other 12v battery that is good, connect it to the charger and jumper cables to both batteries. It works! I've been told you by pass the AGM memory. It may sound crazy, but it has worked for me.
 
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