Originally Posted by
kross57
But the question is, at what age do tires become "bad"? 5 years? 10? Is there a definite age, or are there just too many variables?
IME, waaaaay too many variables to just pick an age limit and call it good.
On the Sears bike I mentioned above, thick, heavy rubber tires on rims meant to be inflated only up to 40 lbs or so, on a bike meant to be ridden slowly by a small person. I'm sure the lady I sold the bike to doesn't put lots of miles on it, but I wouldn't be surprised if she kept the original tires on it.
On a racing bike? With really skinny tires at 120psi? Maybe some really fast descending? Whole different story.