I started using a Battery Tender back about 2000 - plug my bike in Every time I park it in the garage - The Batteries on my Harley's have lasted 5+ years - Plus I have learned that when starting my bike I make sure its in "N" - seems to be easier to start.

 

My 2014 Trike just short of 3 years old 22,000 miles always on a tender. Did the same thing turned over slower and slower. Checked battery 13.1 V hit starter button 11.5. Replaced battery all is good now.

 

Your battery only lasted 3 years and it was always plugged into the Tender?? too bad

 

The previous battery (H-D gell-cell) in my '94 Dyna did 15 years of flawless service before finally givin' up a couple of years ago. I think I got my money's worth out of that one! Replaced it with another one.

It was on a tender most of it's life when the bike wasn't being ridden.

 

Just replaced the battery in my 14 last week because of the same symptoms you've had. Battery was just weak, that's the shortest battery life battery that I've ever had. All is well now though.

 

Just replaced mine yesterday 2,750 miles just bought a month ago. Same problem slow
starting and finally it died at a light . Radio went out restarting and got lucky it started
rode to dealer replaced warranty. They said they replace new ones all the time. I do know my bike set in the showroom a long time and with no tender it caused a bad cell.

 

The remote for my ceiling fan died so I replaced the batteries. It still did not work so I went on eBay looking for a new remote. Decided to check the new batteries before hitting the buy button and one was down on volts compared to the other three, got a new set and all is well.
My 14 SGS is still hanging in there with 11,000 miles but will put a new battery in next Spring, probably a good Yuasa.

 

I replaced mine after a little over 2 years. Batteries + has a Duracell that is more cranking amps than a stock Harley and the warranty is 2 years vs 1. Made right here in the USA.

 

On my previous bikes batteries lasted more then 5 years but those bikes didn't have crap load of electronic stuff. These bikes really need larger capacity batteries to keep up with all the electronic and starting a larger motor. Friend of mine has 14 CVO and it's on 3rd battery replaced under warranty.

 

New battery went in today. Cleaned all connections. The old ones were pretty clean and tight when I took it apart. NO CHANGE. Still cranking slow and sometimes it stops cranking for a half second or so. Voltage still dropping as low as 5.5V while cranking. Any more suggestions?