Fred - I agree with you. I've bought tires individually as they wear for at least 4 years and 3 bikes. I wait until they past the wear indicator, then replace. If that happens while I'm on tour, I may push it another 500-700 miles to get home if the weather is good. Conversely, if I know I'm heading out on a 3K tour, and my tire(s) are close, I'll go ahead and replace them before the trip.
Based on this method, I get 7500 - 8500 out of a rear PR2, and 9500 - 10500 out of a PR2 front. It usually works out to 3 fronts for 4 rears.
Like HotRodZilla - I tried one set of PR3s when I changed both tires at the same time. These lasted 8000 and 9000 IIRC. I don't ride everyday in the rain, so it was back to the PR2, where it's been ever since.
The bottom line is - friggin m/c tires are mucho EXPENSIVE!!!!! I wish they'd come up with the holy grail. Grip out of the ass, but center tread that last 25000 miles.
Of course, I'm reminded of an economics lesson I got one day in college. The professor was very entertaining. He walked in to class with a variety of shaving instruments. He went on and on about the differences between them. We were all wondering what the hell any of this had to do with economics. Then he started telling us about the concepts of marketing. I remember him distinctly saying that "Gilette can make a disposible razor blade that will keep a sharp edge for a year or longer. But if they offered it on the market, the'd be out of business very quickly because they could'nt charge a price high enough to stay in business. They'd rather sell blades that last a week, so you will buy 52 of them every year."
That really stuck with me.
