Anyone getting 8,000-14,000 miles is riding like grandma even if they think they're not. You can't run WOT and get that many miles. I got 4,000 on OE tire (cords peaking), 4,300 on Metzler M3 (could have had more but needed a front so I got a f/r set), now running the Dunlop Qs front and rear and it feels like a completely different bike. Will likely get the 190/55 rear next time around.
If a tire is stored properly (no sun, no excessive heat or cold) it should be fine for years. But on your bike it is exposed to all the elements of the road. If it still has plenty of tread ride it out.
If a tire is stored properly (no sun, no excessive heat or cold) it should be fine for years. But on your bike it is exposed to all the elements of the road. If it still has plenty of tread ride it out.