Race Tire Manufacture Date/Age?

[cee-jay]

Alright, so can anyone enlighten me basically on how old is too old for track tires??

I have a set of Pirelli's on a bike a just purchased, that appear to have dates stamped (inset) on them as 3406, and 2605. From what I understand this small oval's number represent the 34th week of 2006 for instance. These tires haven't seen the track, and have been in a garage for the last 1 1/2 years although they actually look very lightly used. I have the same numbers on Michelin Power Races, but cannot find these numbers or an oval on an older set of rains.

Am I looking at the right numbers, and again, how old is too old?

Thanks,

cj

[tophyr]

Rick @ SB told me last year that tires, properly stored, have a shelf life of 2-3 years. "Properly stored" entails avoiding direct sunlight (UV will damage the rubber) and avoiding extremes in temperature (ie <32F, >120F etc).