Aero helmets are a popular piece of fancy gear that long course triathletes often obsess over. IMtriathlontips.com been down in the A2 wind tunnel care of Blue Competition Cycles to measure their exact aerodynamic advantage. What we learned is that aerodynamics are extremely personal. Helmets that had the longest taper at the back and seemed the most sleek and “aero” sat differently with the natural taper of each riders back. We saw a decrease in wind resistance with a helmet that had a shorter tail on one rider, but the same helmet didn’t work quite as well for another. There’s also the issue of position and what you can hold for an entire 180 kilometers. All in all, it’s very personal. It depends on YOU and how you sit on your bike and hold your head.
When trying helmets on bring your bike (or keep the receipt), get in your aero position and get someone to look at how the helmet fits with the overall line of your body (side profile pictures work the best). You want to avoid a big gap between the tail of the helmet and your back, this will prevent turbulent airflow.
