Hi TheBaldNess & Snowymountainsmick.
I've played with gearing. I found the 14 tooth front OK for 100k's an hour, maybe 110, but any more than that seemed a bit cruel for any length of time. I ended up settling for 15\44, which is 1 more tooth on the back with a stock front. Top speed is more than it ever was & it's quite happy running around in top at 80k's.
Stock gearing was OK. I do most of my riding on the road though. Good on road, ok for fire trails, high for single track. I reckon even a 14 front would be to high for single track, or the stuff I've done on other dirt bikes anyway.
As far as the battery goes, I've got heated grips on my bike & my original battery lasted nearly 3 years & 52000 k's. Pretty good I reckon.
If you're thinking of buying 1, be aware of the oil consumption issues. If I had have been aware of them before I bought the bike, I would have bought a DR650. But I bought the KLR, & now I wouldn't swap it for anything. Mine uses about 400ml per 1000km around town, less on a run. I recently did the Imbil Rally at Queensland. 3500km round trip & I used about 600ml of oil. It's always used oil so I figure there's nothing to worry about. I probably didn't run it in hard enough to bed the rings.
The Baldness may be able to fill u in on his first impressions of the bike, he's just bought 1.