when is it worth replacing your tire?

how are they in the wet?

i replaced the tire

and stopped eating all that poutine

Vredestein Update: Since I posted two weeks ago, a clubmate saw all the rips in my tyres and said I ought to replace them before I got a puncture. On Friday I was in the middle of nowhere doing a 54-mile ride in the New Forest in the rain when I got a puncture in my back tyre. Fortunately I managed to change the inner tube and carry on: I feared I wouldn't be able to get the last 10cm of tyre back over the rim (this has been a constant thumb-wrecking problem for me in the past), but this wasn't a problem - maybe the tyre gets more pliable after a lot of use?

Anyway, I decided enough was enough and bought myself another couple of tyres (Vredestein Fortezza Tricomp again) at a worrying cost of £72. I've just finished putting them on, at great cost to my thumbs. I've just checked my nerdy ride log spreadsheet and worked out that the last pair of tyres had only done 1,554 miles. Does that sound like a reasonable amount, or is that a bit on the low side?

My Ultremos don't seem to manage over about 2000 miles before getting too cut up to keep. But they're lightweight racing tyres that aren't meant for endurance. So it does sound a bit on the low side, but then you have no idea whether you got a puncture because the tyre was cut up (answer: probably not unless the holes are really big).

2000 miles is a lot for ultremos!

Yeah, I just replaced the last one after 1600 miles - with a Stelvio Raceguard for, I hope a bit more protection and durability.