For a future article--need to include more info on tire construction:
When choosing your tires, you need to consider a couple of variables—matching the tire to your rim width; matching the tire’s construction to your intended use.
On matching the tire to your rim width—this is very important for aerodynamics, especially for your front wheel. What you want to do is make sure that the width of your tire matches the width of your rim, to smooth so that there are no abrupt transitions for airflow as it passes over the front and rear of your wheel. Choosing a tire that’s too narrow (not likely, but possible) or too wide (much more common these days) can largely cancel out the aero advantage of a wheel. In other words, you can spend a couple of thousand on aero wheels, choose a poor tire match, and end up with a wheel combination slower than the wheels on which you train.
Tire construction—this is difficult, as choosing a tire for durability and puncture resistance will run contrary to choosing a tire with minimum rolling resistance. When racing, you want a tire that rolls as fast as possible; on the other hand, if you flat, your ride is going to be pretty slow ;) What you want to look for are tires with the highest TPI value that you can find, as this generally means that the tire will be very supple. A tire that’s supple will have less rolling resistance as it travels over a road’s surface; the term of this is hysteresis (and I’m pretty sure that I got the spelling wrong on this!); similarly, even tube selection plays an important part in choosing a race setup, with latex tubes having a lower hysteresis than standard butyl tubes.
I’m assuming that you’re talking about clincher tires, not tubulars. Tubulars can have the lowest rolling resistance of all, provided that they are glued to the rim with a hard interface. This is kinda complicated, and I’ve a two year old pulling at me right now, so more on this another time. For clinchers, the tires that generally test the fastest in terms of rolling resistance are the high end offerings from Veloflex; from Vittoria (and Zipp, which are rebranded Vittoria’s); from Michelin (Pro Race); and Cont’s Supersonic.
Of the tires above, I’ve found that the Michelin’s offer the best compromise between durability and performance; I really like the Veloflexs and Vittorias, but they are not as durable—but they really are fast. If I’m racing a highest priority event on very good surfaces—say an hour on the track—then I’d go for the Conti Supersonics, but they have a life of no more than 250 miles or so—they are fragile!
Finally, I’ve found blue tires to be the fastest!