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Battery Charger

I use a Battery Tender on my bike 100% in the garage. OE battery lasts 3 years.

That is because they are being overcharged big time at the ambient temperatures they are being charged at, both while parked and while driven. Once again, a voltage regulator issue because it does not temperature compensate.


Get an Optima. Never had one less than 5 in a car.

And yet we read about them failing prematurely on various forums. :scratch

You say they fail due to the heat down there. My battery sits in my car during the 6 weeks I'm off touring (last summer...10 weeks) and I know the temps are up there while it is parked outside; yet it has passed its 10th year and has a hard life on top of it. Since when do cars down there have to start when it is -10??F outside? Talk about a current draw!
 
That is because they are being overcharged big time at the ambient temperatures they are being charged at, both while parked and while driven. Once again, a voltage regulator issue because it does not temperature compensate.




And yet we read about them failing prematurely on various forums. :scratch

You say they fail due to the heat down there. My battery sits in my car during the 6 weeks I'm off touring (last summer...10 weeks) and I know the temps are up there while it is parked outside; yet it has passed its 10th year and has a hard life on top of it. Since when do cars down there have to start when it is -10??F outside? Talk about a current draw!

A dead Optima will take a charge when nothing else will. That may be why they last 2-6X an OE battery.

I beg to differ on my bike being overcharged. After plugging it in, most times, it goes from red light (full charge) to green light (low level charge) in 15-30 seconds and stays there.

Compare that to if I ride, and forget to plug it in for a few days or a week. The transistion then could 30-40 minutes.
 
I beg to differ on my bike being overcharged.

You mean your battery.

If the temperature is what you say it is (115??F) and if the voltage regulator does not compensate for that, and it likely does not, then your battery is being overcharged....and therefore gassing.

Voltage regulators usually cut out at 14.4V. At the above temperature, you should be charging to about 13.9V for an AGM battery and even far less for a GEL battery.

Source: East Penn Technical Manual.
 
Only hot (over 110) in late June through July. By then, the charger will be in low charge.

The trick to know is when to connect and charge. All winter we're fine, it's only the heat season, we have to be selective when to charge.
 
No Simple Answers?

So for the BMW OE battery, is there any consensus on the best charger?:D
 
I have an old BMW Schumacher charger that came with my K75. It puts out about 2 amps on a low battery, drops to 0.5A when charged. It is a dumb charger and will not shut off.

At that current will it hurt the stock battery in my R1200R?

My dealer says no problem, as long as I connect it direct to the posts.

Scott
 
Scott,
As long as you only use it for a couple of hours it will be fine. If you leave it
connected, it will kill your battery in short order. Get a Battery Tender and
leave it connected at all times you are not riding. That will extend your battery
life as long as possible.
 
Well, I;m going to ask a couple more questions regarding battery charging. I recently picked up a 1999 R1100 RT-P with 29,600 miles. There is an Odyssey 680 for the main battery and another brand for the second battery.

I went for a 100 mile ride on Saturday and everything was running fine. I pulled off the fairings this afternoon to change all fluids (I had not plugged in the battery in the meantime). After the fairing was off, I went to start the bilke and it turned over very slowly and did not start. I plugged it in and it went to the green light within about 5 minutes (I have a Yuasa Smart Shot, 1.5 amp charger rated for AGM batteries).

I need to disconnect the batteries, clean all terminals and reconnect and make sure that everything is tight. I also need to get all of the way into the batteries and see if I can find any dates on them. I may end up getting a new battery
Here are my questions:

1) I noticed that I had left the switch in the park position. Is this enough to pull the voltage down in two days? The key does not come out when in the off position.

2) Is it a problem charging through the accessory charger on this bike (this is not a CanBus bike)? The Clymer manual indicates that this is a problem to some of the electronics, but if the ignition switch is off I don't understand how this can happen (other than to the clock).

I have a call in to the police department that used to have the bike to see if I can get any other maintenance records which hopefully could include information on the batteries.

Thanks in advance for the help.
 
?1- yes, 2 days would be plenty enough time to make your battery ill. i would think that key should definitely be able to come out in teh off position. have never heard of one being unable to- but i don't know RTPs.
?2- no problem charging thru port- it's the only way i do mine.
 
charger

My battery dealer says I should use a CTEK charger with my Odyssey batteries.
Why wouldn't my Deltran charger be just as good ? Or is he just trying to sell me a CTEK ?

If your Deltran charger is auto-sensing, it should not matter. The Deltran auto-sensing charger drops to a trickle after 90 percent and turns off at 100 percent. Sounds like a sales job.:)
 
Well, I;m going to ask a couple more questions regarding battery charging. I recently picked up a 1999 R1100 RT-P with 29,600 miles. There is an Odyssey 680 for the main battery and another brand for the second battery.

I went for a 100 mile ride on Saturday and everything was running fine. I pulled off the fairings this afternoon to change all fluids (I had not plugged in the battery in the meantime). After the fairing was off, I went to start the bilke and it turned over very slowly and did not start. I plugged it in and it went to the green light within about 5 minutes (I have a Yuasa Smart Shot, 1.5 amp charger rated for AGM batteries).

I need to disconnect the batteries, clean all terminals and reconnect and make sure that everything is tight. I also need to get all of the way into the batteries and see if I can find any dates on them. I may end up getting a new battery
Here are my questions:

1) I noticed that I had left the switch in the park position. Is this enough to pull the voltage down in two days? The key does not come out when in the off position.

2) Is it a problem charging through the accessory charger on this bike (this is not a CanBus bike)? The Clymer manual indicates that this is a problem to some of the electronics, but if the ignition switch is off I don't understand how this can happen (other than to the clock).

I have a call in to the police department that used to have the bike to see if I can get any other maintenance records which hopefully could include information on the batteries.

Thanks in advance for the help.



Hello Efoltyn. I have a 2002 R1150RTP and may be able to answer your questions:

1. You should be able to remove the key in the off position. Park position, if I am understanding this right, just locks the steering.

2. You can charge through the accessories socket. That is how I do it as well. I am not sure on the R1100RTPs if you have two accessory sockets. On the 1150rtps you do. The foward socket pulls from the secondary battery while the back socket pulls from the primary or starter battery. I use a dual bank Battery Tender plug into both to keep them charged.

Hope this helps! :help
 
Do you change the charger/alternator on your motorcycle when you change batteries?

It's the same charging system.
 
Do you change the charger/alternator on your motorcycle when you change batteries?

No, but ideally you would have an adjustable voltage regulator that could be set to the requirements of the particular battery. In most cases, it does not matter, but there are a few that do need higher and lower charging end voltages.

More of a concern is the temperature. At freezing, you could charge a battery to 15V; at 100F, that would be limited to about 13.8V. Your voltage regulator does not have temperature feedback...unfortunately; professional bench top charging systems do.
 
Brewmeister,
You live in a colder area (relative to the SW), so that could account for the longer batt life. My oldest was over 8 yrs., but this was a flooded type batt - a type I feel should not be used in M/C applications these days.
You stated 6-7 yr. batt life. Was this life w/ AGMs, gel, or flooded? I'm curious as to how long an AGM will live relative to climate, but I don't think there's enough history w/ them. Well, maybe in Phoenix....
 
No, but ideally you would have an adjustable voltage regulator that could be set to the requirements of the particular battery. In most cases, it does not matter, but there are a few that do need higher and lower charging end voltages.

I don't disagree completely, but suspect that then folks would turn the voltage up, cook their battery, and shorten rather than lengthen battery life. If you ever happened to have an F650 Funduro you didn't even need something adjustable to do this: BMW/Rotax/Bosch accomplished it without any rider intervention.
 
I don't disagree completely, but suspect that then folks would turn the voltage up, cook their battery, and shorten rather than lengthen battery life.

Well they are already being cooked in TX, AZ and those areas in the summer due to the factory setting being too high for the temperatures. I don't think you'll find too many batteries with a long life down there.
 
Well they are already being cooked in TX, AZ and those areas in the summer due to the factory setting being too high for the temperatures. I don't think you'll find too many batteries with a long life down there.

are you talking about BMW factory settings on the bike's charging system, or about the charger's settings?

heat kills batteries faster than cold does. car and bike batteries have a much shorter working life in the heat of AZ, whether they are chargered or not.
 
Borned and raised in NY, grad school in Chicago, and then to AZ to defrost. Here in AZ since 1981.

Heat does kill a battery much worse than cold. In cold you get a whr, whr, whr when a battery is low. Here, we may get a click, and then nothing.

So many batteries go in August, it can be hard to get one if you need one. You can't charge one up or jump it here from that, there's nothing left.
 
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