I've changed tires twice in the 7+ yrs I've had my bike, the first time when I bought the bike at 7K on the clock. The last Dunlop (don't recall model) rear was still usable, but getting pretty down there last March, so that would be 17K miles on that set. Both times I've replaced front at the same time regardless the wear on the front. I may change that in the future to 2:1, but only time will tell.
Well I do know I won't be buying Kendras again.....I put the rear one that's on their now the same exact time last year and 4k miles later it's SHOT ! I got back from a ride Sunday nite and just looked down and could see the inners of the tire in a couple spots
Even though the front looks like it has some life in it I'll probably replace it too.
Obviously I'm not gonna ride it ANYWERE at all as bad as the rear is now....I'll either wait and trailer it to Blue Fox's house after Labor Day and we'll do it along with my head bearings or if I get itchy and just HAVE TO RIDE before then I'll take the wheels off and take just them to a dealer to mount.