Charge the battery on a tender until it is fully charged. Disconnect the charger for about 2 hours check battery with a volt meter. If it is 12.8 or higher it can be load tested and chances it is fine. If it is below 12.8 it is getting weak, will still last for quite awhile if you keep it charged. Of course if you have a load tester then you will know for sure.

 

Mine is three+.. expecting three more.
I ve read in here some lasting 7yrs, probably average 5-6 with normal use during summer riding couple times a week over 45minutes or so, and on tender in storage.

 

You really need a load tester, but they're cheap. A battery can have the appropriate voltage but not be able to deliver the amps when needed.

 

You can stop at any Autozone or Advance auto and they will load test your battery right in the bike for free.

 

They do provide the service, but that test wouldn't tell you that the battery is low (unable to deliver the needed power) because of another component in the charging system failing. Best to test the battery with a full charge.

 

The one on my '02 Ultra is 8 years old, and still PLENTY strong! ...... I've never before had any battery, on anything, equal that!

 

In my experience, the battery will last about 15 hours, if you leave the ignition on over night. DOH!

 

just bought a new ODYSSEY battery from westcoast batteries for my FatBagger. the OE battery was getting a bit weak & the cool part about the new one is, it's an inch shorter than OE, & if you do add-ons it gives a bit more space under the seat for wiring or those bigass connectors, if your mod is plug-n-play

http://www.odysseybatteries.com/battery/pc545mj.htm

 

5 years

 

I replace mine every three years. I ride almost year around. A bad or going bad battery with cause havock on the rest of the charging system also. So its cheap insurance.