How it’s tested
The second most important attribute of a tri race tire, in our opinion, is puncture protection. To measure a tire’s puncture resistance, Wheel Energy presses a small dowel into the tire with increasing force until it punches through and flats the tire, then records the force required to break through.
Specialized was able to test the effectiveness of various types of puncture resistant layers to evaluate their effectiveness. These layers also tend to increase rolling resistance. Specialized found that tire casings with larger threads (low TPI) tend to be more puncture resistant than those built with thinner threads.
The test for puncture protection reveals that tires with moderate TPI count are resilient to flats. The rolling resistance test shows that tires with such casing also have low coefficients of rolling resistance. The results of Specialized’s tests reveal that this style of tire, not a tire with ultra-high TPI, is best suited to the specific needs of triathletes.