When Tom Zirbel jumps on his bike Friday in Aguascalientes, Mexico, for his US Hour Record attempt, he'll be on familiar ground. Zirbel will attempt to beat Norman Alvis' decades old mark of 51.505km on his road time trial bike - a Rally Cycling team issue Diamondback Serios - outfitted for the track.
Zirbel has found a lot of success this season on his red-and-black aero machine, including time trial wins at Tour of the Gila, the North Star Grand Prix and the Cascade Cycling Classic, and a runner-up finish at the USA Cycling Pro time trial championships behind BMC's Taylor Phinney.
The SRAM Red brakes and gearing have been removed of course, replaced with a 53-tooth ring on the fron and a 13-tooch cog on the back. The rear disc is fitted with a special hub that allows the mechanics to adjust the chain tensions, but outside of those small changes, the bikes is exactly the same as what Zirbel rides in time trials on the road.
Take a look at Zirbel's bike specs below, and then click or swipe through the gallery above for a look at Zirbel's Hour Record ride.