BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

As I do every winter (since I ride my bike year round) I changed my oil to a lighter 10w-40 oil to help with cold starting, but even after switching to the lighter oil my battery still struggled to start the bike when it was colder outside (usually anything below 20 degrees). The battery I'm using now is a Westco battery from beemerboneyard which was installed on March 9th of 2010. So while it was still freezing outside I went ahead and ordered a new battery from beemerboneyard because I saw they were on sale and was pretty sure I needed a new one. However, it has since warmed up quite a bit here in Missouri and is now in the 40's or 50's every day. Since it warmed up the bike fires right up with no problems at all.

So...my question is, how long does an unused battery stay good? Can I just leave it sitting in the garage or should I buy a battery tender to hook it up to until I need it? OR, should I just go ahead and switch the batteries out now even though the one I have now seems to be perfectly fine after the weather warmed up a little?

I'm no expert.....I would have the battery tested to see what kind of state it really is in. If it was fine, I would call beemerbonyard to see if those batteries are fully charged when they send them out or if they need to be charged by the consumer when they get it. That may be the answer to the next question as too how long that battery can sit on the shelf and what you need to do (if anything) to it while it sits on the shelf. I would be interested in their answer as I have thought of keeping a battery around as a back-up as well.

Batteries should never be left to stand once filled and charged. If they are neglected in this way
they suffer from a build up of lead sulfate which can short out the plates or cause severe self-discharge
characteristics. A good modern battery tender will keep the battery's cells in good condition by constant
charge / discharge / load cycles. I use an Optimate4. These chargers can also rescue batteries damaged by neglect.
For some further information try here:

http://www.visordown.com/product-featur ... historysub
HTH

Beemerboneyard got back with me and told me pretty much the same thing Ol' Jeffers said, that an unused battery should be put on a trickle charger if I'm not going to use it in the next two months. So I may just get one of those because I could use it on my KLX351 the rest of the time. I ride the BMW year round, but the KLX sits around a lot during the cold months.