I ride a 2013 RT Ltd that was manufactured sometime in the first half of 2013 & hit the streets in Oct 2013, since then it has done well over 38K miles and it still runs the original YUASA battery.
My Spyder experiences a wide range of temperatures (-10°C to about 50°C) temp extremes which I'm told are pretty tough on batteries, and it is pretty much at its limit for running electrical accessories as it has the older magneto style charging system. I very rarely think about putting it on a battery tender & whenever I do I usually just sit down for a while & wait for the feeling to pass.

On the odd occasion I don't just sit & wait for a bit, I simply ignore that thought.
I did spend a couple of months not ryding at all a couple of years back due to unavoidable medical issues, & when I tried to start the Spyder after that break it really didn't want to play at all, so I connected it up to a CTEK charger & let it charge for a couple of hours before trying again. It started fine after that so I carried on ryding & haven't had any issues since. It generally sits for only a day ot two between rydes, but every now & then it might sit for a week or so, but rarely any longer than that; and whenever I ryde it is usually for a couple of hours at least - sometimes a couple of weeks!

hyea:
Recently, it dawned on me that my Spyder was still on the original battery so I took the Spyder down to my local Battery World & had the battery load tested - it passed with flying colours, so well in fact that the Battery Bloke compared it to one of the new 'factory filled' & then properly charged jobbies they had recently put on their shelves and the readings from mine was almost identical, only a little better than the brand new unused units..... so he compared mine to a few more - same result. :2thumbs:
So on his recommendation I'm not going to change my battery just yet, and maybe you don't actually need to change yours just yet either JKM - but I'd strongly suggest that you too get your battery load tested before you make up your mind! You might be pleasantly surprised like I was - or not! :shocked: But whatever way, by getting that load test done, you'll KNOW if it needs changing or not! :thumbup: