Bontrager Race X Lite Aero TT: fastest clincher?

Yeah, but what does Lance think?

Bontrager, a component brand made famous by Lance Armstrong’s multiple Tour de France victories and now co-sponsor of his Team Astana, has introduced the US$59 Race X Lite Aero TT tyre, one it’s boasting to be the fastest clincher available.


According to Bontrager brand manager Chris Clinton, the Wisconsin-based company designed this tyre a little over a year ago and tweaked the dual silica compound a little late last year.

“However, we hadn’t tested the new compound for rolling resistance,” he told BikeRadar. “Recently, we set out to design the ‘World’s Fastest Tyre’ and created an all new tyre. Turns out in testing that the current tyre, with the slight modifications, was actually the fastest! Thus, we have had the ‘World’s Fastest Tyre’ for over a year and are just now getting the word out.”

Comparative images between tubulars and clinchers.: comparative images between tubulars and clinchers.

Clinton added that testing occurs at the low speed wind tunnel at the San Diego Air & Space Technology Center, the same place where Armstrong and his Astana teammates Levi Leipheimer and Alberto Contador worked on their time trial positions last November.

“We tested for both aerodynamics and rolling resistance,” Clinton said, “putting this tyre up against the competition. It did not disappoint. In fact, once you hit 17 mph (with a 10 mph headwind) you start to shave seconds off your ride compared to the next best-in-class tyre. We’re talking about an increase of 6.37 seconds in a 10k time trial, 31 seconds in a 40k time trial, and more than three minutes during an Ironman triathlon cycling leg.”

Wind tunnel testing results from san diego.: wind tunnel testing results from san diego.

Bontrager tested its 120tpi, Aramid folding bead Race X Lite Aero TT 700×19 clincher against the Zipp Tangente, Continental GP4000 Black Chili, Veloflex, Schwalbe Ultremo, and Michelin ProRace3. It claims a 180g weight for the 700×19 version, 195g for 700×23, and 200g for 700×25.

Surely with all this data, Astana will be using the tyre this year?

“No,” Clinton said. “They are a tubular team through and through. Though we have chatted about the benefits of the Race X Lite, the Astana team prefer the time-tested performance of tubulars. Thus they ride our Race XXX Lite tubulars.

“For 2009, the Timex team will be rolling on Race X Lite Aero TT clinchers at Ironman triathlons, 70.3 Ironmans and other multisport events,” he added.


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