Motorcycle Repair: 2000 BMW R1200C Battery and overheating, bmw r1200c, bmw shop

Question
My battery is dead, and the local BMW shop said it would be around $200 to install a new battery.  The battery alone is $90.  This seems a bit ridiculous.  I could get 4 new 900 amp batteries installed in my truck for $200. I know you have to take the gas tank off to get to the battery, but can I do this myself?  You can't charge it or jump it, because you can't get to it, and the only battery access on an R1200C is a little plastic two-prong thing under the left sideplate, and no charger known to man has the male plug to fit.  Is there an adapter or something available in case it ever needs a jump?  I guess I'll install a standard 12-volt plug (for $50, again ridiculous) so I can at least use a standard trickle charger in the future.  I just moved, and my bike is sitting in my ex-garage, all by itself.  I need to do something pretty quick.  I also discovered that you can't pucsh-start it when the battery is dead, since it has electronic ignition and fuel pump.  

One other thing.  I last started my bike about a month ago, just to move it around and run it a bit.  I got distracted by a visitor, and the bike was left running.  I guess it overheated and shut down, because it wasn't running when I got back (about 15 minutes), and I guess the headlight drained the battery when the engine shut off, and the heat probably did the battery in, anyway.  Do you think the engine was damaged by the overheating?  Is there an automatic thermal shutoff?  There are no leaks, and it turns over (a little) when you crank it (then the residual charge in the battery goes).

Answer
Hi Michael,

The best advice I can offer is to purchase the service manual & parts microfiche and do the work at home.

Batteries are expensive, especially Yuasa brand. Decka brand is by Yuasa and are quality. Exide is another decent brand. I would remove or fabricate a new plug as you mentioned for charging. You can buy the $75 plug kit, but I know how you feel about that.

To determine if there is engine damage from overheating, perform cylinder compression and leak-down tests. This will indicate cooked head gaskets, etc... Check for coolant in the engine oil and vice-versa.

Don't know of a thermal protection shut-off.

There ignition system needs min. 12.6 VDC to operate properly.

Do an internet search for BMW owners message boards and forums. Maybe someone there has a simple fix for your electric plug modification needs.

Respectfully,
Mark Shively