I replace mine every 4 years....don't want to take a chance. Spending $80 to prevent a problem is well worth the cost. I might have given away a few years, but I've never been stranded.

 

My '06 stock battery lasted 3 andhalf years before I had to replace it.

 

Still crankin' since 9-3-05 on my '06 FLHTCI.

 

This just came up a couple of weeks ago iirc. I replaced the original in my '00 in '05, not because it needed it, but because I didn't trust it... I was used to the old flooded style bats I had in my old shovel that never lasted more than 2 years.
The replacement is still in there going strong. I may leave it the rest of this season then replace it next spring.

My bike lives in an outdoor shed with no power. I try to run an extension cord out there once a month in the winter to top the battery off with a Battery Tender.

 

Nearly 4 years and on a tender alot. Don't know if that makes a difference.

 

I ride almost every day. My 02 battery lasted 4 years/60,000 miles. My 07 is almost three years old (august) and shows no sign of weakening. I do have a battery tender for those few days in a row during the winter, but not regularly. I think regular riding keeps the battery in good order.

 

Had 7 years on one and just replaced it because the starter drive was going out and the battery tested low so I replaced it too. Was never on a tender of any kind.

 

Mine is 4 years old, Harley Dealer replacement and I can tell its not quite the same as last year. With key off it shows a fully charged battery at 12.5 volts. Running at 14.7 or so volts. Ever now and then I get a slow turn before engine starts catching and the engine fire helps the starter along. Been watching it by hooking the tender leads to my DC volt meter. When I hit the starter the volts are dropping to 8.6 volts. I have read it should not drop below 9.6 with headlight,marker and starter draw. Thinking since I have to pull the seat to jump it it is not what I want to do since I leave work at 12:30AM. Harley wants $116.95 for another gel. Is there a cheaper but reliable alternative for my 04 Softail

 

Used to haveto replace every 3 years or less on my Evo. But then Harley started using better battery technology and voila - 5 to 7 years. I changed my Softail battery after 6 years as a precaution before going to Alaska. The touring batteries might last longer since they aren't subjected to being surrounded by hot oil. But of course there's more load on the touring batteries (lights, radio etc).

 

4 years on the FLHTI, then occasionally starter stall, didn't want to be stranded in desert so replaced. Always on tender. Buell SW1 White Lightning made it 5 years, then died overnight despite battery tender useage. Buell has 19 agw Dyna battery.