13 year old battery

[limax2]

Just replaced the original battery on the January 2001 registered FZS600 so it must be about 13 years old. That seems pretty good to me.
It never let me down but I've noticed recently that if the bike failed to fire up first stab it was turning over slower on the next go. Decided it was time to go before my next camping trip where it gets used to blow up the air bed.
After recommendations on here I've gone for a Motobatt AGM type. Be happy if that lasts as long  .

[Fazerider]

Those original batteries seem to last very well, at least on bikes that are used regularly and don't have an alarm to drain them... mine still spins the engine up with no problem after 15 winters.