Q: When is it time for new bike tires?
A: When your old ones disintegrate to the point that your green tubes poke out of about a dozen holes all around the sidewall.
I guess 5 years is too much to expect out of stock tires, huh. The good news is that I scored a new set of Kevlar Panaracer Smoke/Dart tires for half price at Performance. I installed them, cleaned and regreased the front bearings and tightened the front wheel of the ol' singlespeed today. Hopefully I'll get out for a ride tomorrow. It's been over a week since my last ride.