“The guy I was working with in the GM aero program was really a great mentor. He taught me to think outside the box and not be afraid to try things and really explore my creativity,” said Hall, who now focus on innovation and continuous improvement across SRAM. “A lot of aero development, sometimes you can’t necessarily explain the result. So it’s about perseverance and testing and a lot of times it’s trial and error. You learn something, it builds a little bit of knowledge, and you continue to evolve.”
Downforce and Side Force
Working within the tight car specifications of Indy car, Hall looked for any aero advantage. For a time, mirrors were outside of the required car specs. So, Hall and his team started making the racing car’s mirrors into aero wings.
“We were able to create considerably more downforce on the car by treating the mirror as a wing,” Hall said. “That was kind of a highlight. What we did really spawned development across the whole grid and made them actually change the rules. Now there’s a certain dimension the mirrors can’t exceed.”
Hall was determined to find new challenges, a search that eventually led him to apply for an engineering position with Zipp in 2005. He immediately saw motorsports’ influence on the company. “I was really intrigued by what they were able to do in the factory. Zipp had developed a manufacturing process from scratch, built their own machines, really tailor-made for the production of carbon wheels,” he said. “Zipp grew up in the same city with all these other really creative, industrious people.”
In joining Zipp, Hall evolved from a car guy to a bike guy. Designing bicycle wheels, he looks to lessons learned from the motorsports. Thinking back to how he had to account for “dirty air” in auto racing, he started considering the effect of the turbulence caused by pedaling and crosswinds. This prompted him to study the back half of the wheel, or as Zipp refers to it, “the second leading edge.” That focus resulted in Firecrest rim technology, first introduced in 2010.