I have reviewed all the various battery threads out there and these symptoms - while common to some threads - are a little different.
Background: 2005 LT w/68k miles. New in September 2005; in August 2007 installed a new Odyssey PC680 battery @ 38.5k miles, equalling 15 months and approx. 30k miles on this replacement battery to date. Bike is ridden to work (75 miles RT) year-round except when ice/snow are present or forecast. The bike is on a Battery Tender in an unheated garage whenever it's not being ridden. Battery Tender is connected via the 12v outlet on the bike's port side. Bike faces south when parked.
Symptoms: The past few months the battery has become unreliable. I have been carrying jumper cables with me and have had to be jump-started several times. It started weakly (which I define as the battery sounding like it's barely going to get it started). I have babied the battery when two-up by turning off heated gear, accessories, radio, etc. when approaching an interstate exit, as it seemed to need the extra power to restart after refueling, for example.
The headlight dims noticeably when at idle, and returns to normal intensity at higher RPMs.
The bike has not been ridden for 4 weeks due to weather. I have not been able to start it for the last 2 weeks, whether the temps were in the teens or 50F. The cockpit lights come on, the charge light comes on (thanks, David Shealey), and it cranks weakly several times but runs out of juice very quickly and fails to start. Two episodes of that and thene there is not enough power to crank. The Battery Tender light shows green - a full charge - during all of this. One thing I have not tried is pulling the clutch lever while cranking.
If all of this points to replacing the battery, that's fine - I can do that. I've read all your recommendations. Do I need to be concerned with CCA (for Ohio winters) or amp-hours (battery capacity)? With the amount of additional lighting I have, plus radio, GPS, and heated gear X 2 it seems amp-hours is more important to me.
Is there something else
causing these problems other than a weak/dying/dead battery?