Originally Posted by
ahsposo
There's a difference between tires used for training and racing. Most of us are out here for the exercise and the fun of riding a bike and probably have budget concerns. TDF riders have flats and have a support vehicle to get 'em back racing. What I think the OP and most of us are seeking is that balance of decent road feel, durability and ruggedness. Light weight tires and wheels are easier to accelerate. Having said that smooth rolling heavy tires have inertia. The comments about the Conti Ultra Sport approaching Perpetual Motion may have something to due with the claimed weight of 340g for the wire bead or 270g for the folder vs. 205 for the GP 4000 (folder only)
I had a similar theory about the inertia of heavy tires when I was riding a 27 incher road bike. I don't know what I did with the excel sheet, but it turns out that as soon as you factor in wind resistance above about 18 mph (depending on rider weight), any rolling inertia you gain from heavier tires is quickly eaten up by drag. Basically heavier tires make you fight the wind more on each pedal stroke than they do maintain linear momentum. Now, on a 7% downhill grade, the weight quickly becomes and advantage. I'll see if I can find the excel sheet. I figured it out when I was waiting for a flight for about 4 hours one day...
For cost-effective tires, the Nashbar Prima Plus 2's do well, as long as their priced ~$10. They're not particularly good in any category, but are a nice balance of ride quality, performance and durability. They'd certainly be a good, cheap training or recreational tires.
EDIT: I do remember that I assumed the rider was a wedge for the purposes of calculating drag, which was probably generous. The actual drag is probably quite a bit more.