Battery died, unable to recharge? Yeah, you need a battery, but...do you know *why* it died? That's what you really need to fix. In fact, if you fix that, you may not need a new battery. (Unlikely, but possible.)
Well this battery came with the bike (2007 DL650) when I bought it 2 years ago with 50K miles on the bike. I let it discharge mot of the way a few times while I owned it (well 2 times at least) when the bike was in the shed (no battery tender). So I didn't take quite as good care of it as I should have. It might still be good if I would have taken care of it.
The battery is a GS YUASA YTX12-BS I see it goes for about $99 online. I am not sure how to decypher the manufacture date, I do see some numbers on the battery. 311205e3
Also I just recall that even when I firt bought the bike, if it stalled while dirt riding, when I try to start it right away; a pause and then it would barely turn it over. A hot start when thee bike sits for a minute, it starts right up like normal. Maybe it's the compression on a hot start right after a stall. So there was that symptom, but I checked it did not need charged that day. So it looks like we got our money's worth out of this battery, it had given me some red flags and I just kept using it. Because it charged like a normal battery until just recently.
I was in my shed getting ready for a road trip the next day. Suddenly this thought comes into my mind, says "You're gonna break down" (a spirit). I hadn't checked my oil in a while, thought the bike wasn't using any. Then I checked it, it was low. Had to start bike, wait, check oil, add more. Did that 5 times it was a half quart low. Next morning; battery was toast. Hook it up to the charger, 1 minute later it says it's charged all the way. Had me goin....thought it was good. Eventually I hooked up my Halo jump starter, the bike started right up. So that's how I found out it was the battery. That spirit was right; I did break down.