stapfam

Many signs that a tyre is worn out and the obvious one is visual. You may be lucky enough to run a tyre down to the canvass without the other problem coming in of an increase of punctures. That is the main sign I get that a tyre has less rubber on it for optimum use as less rubber for Thorns etc to penetrate is a sure sign that a tyre is getting worn. Rear tyres will be the one to show wear first and a definite flat area across the tread is giveaway that the tyre is past its best. This is the time to start looking for a new tyre (s) and I normally take the front tyre and put this on the back- and put the new tyre on the front. I only buy one replacement tyre at a time- mainly for expense- but also there may be a newer tyre out that I would like to try at sometime but if I have a "Spare" new tyre on the shelf- I would be loath to change. Tyres are like many bike components and they do get improved over the years.

And worn tyres get chucked. I have taken them off the bike because I don't want to use it- so why keep it?

And KR2--I had to upgrade to PR3's from PR2's as the 2's are no longer available. Haven't seen any increase in wear or performance- But my son-in-law that runs PR2's cannot keep up with me on the fast downhills. He has to back off for the curves- but that may be down to the rider and not the tyres. I chose Michelins over Conti's initially as I have had a few worries over the sidewall shedding threads on the Conti's previously. But from what I have heard- the tyre performance and life is about the same between the PR3's and the 4000s'