Gear Review: Easton EC90 Aero 55 Wheels


Easton contends that while many brands claim to be the fastest, they are quick to trot out the trend that their "fastest" looks sharp within a narrow yaw angle constrainment. That's great when the wind hits you only between 17 and 19 degrees, but it doesn't represent the full range of wind angles we experience on the road. "It's hard to say 'aw, I'm gonna take out my 17.5 degree yaw wheels for this ride or race,'" says Easton product manager Scott Junker.

So instead of claiming to be fastest within one yaw, Easton developed the EC90 Aero 55 to be an all-arounder; Easton isn't claiming to be the fastest wheel at an acute range; they're claiming their wheel as most adept (and thusly, the best handling wheel) at all ranges. Consider the Aero 55 the utility of the race wheel world.

To gather that "jack of all trades" moniker, Easton applied a study analysis called Wind Average Drag (WAD). The formula has been in use by the automotive industry for decades, and now stands as Easton's metric for finding the wheel's aerodynamic performance across a range of yaw angles, from zero to 20 degrees.

"WAD takes into account a lot of wind angles, wheel speeds, wind speeds and assigns them a weighted average drag number," Junker said. "We said zero yaw, we don't need to worry too much about that; let's put a lot of importance on tests at these more frequent side angles.

Testing speed was also done at both an "industry standard" 30 miles per hour as well as 25. "The average age group bike split is under 25 miles per hour, so why are we testing at 30?" Junker said.

Their results? With testing executed at the San Diego Wind Tunnel, with all tires set up on Continental Podium 22 tubular tires on a BMC TM01 frame and fork as a baseline, The Aero 55 came in with a weighted Wind Average Drag average (at 30 mph) of 371 grams for the Aero 55 tubular, and 381 with the Aero 55 clincher. Easton's comparatives found a WAD number of 411 grams for a Enve 6.7 tubular wheelset, 422 for the Hed Stinger 5 tubular, 426 for the Zipp 404 Firecrest tubular and 458 for its own previous aero wheel in the category, the Easton EC90 Aero tubular.

The drag savings of the Aero 55 against their baseline EC90 Aero added up by their estimation to 32 seconds over 40K of riding.

Tire-Type Options

Again, Easton provides a new option. As one would expect, the Aero 55 is available in tubular and carbon clincher versions. But a new twist is that the carbon clincher version is also certified tubeless compatible. While Corima debuted the tubeless-compatible Aero+ carbon clincher over a year ago, it never saw store shelves. As such, Easton can fairly claim that they will have the world's first production tubeless-ready carbon clincher.

The Aero 55 tubular will tip the scales at 1,330 grams for the pair, while the tubeless-ready carbon clincher will weigh in at 1,580 grams.

More: 3 Steps to a Faster Bike Split

  • 3
  • of
  • 4

About the Author

Jay Prasuhn

LAVA magazine Senior Editor Jay Prasuhn has served as a technical, feature and destination writer for more than 13 years, covering and photographing events including the Hawaii Ironman, the Olympic Games and the Tour de France, as well as IndyCar and NASCAR motorsports events. An Ironman, ultramarathon and Leadville 100 MTB finisher, Prasuhn makes his home in Encinitas, Calif. You can follow him on Twitter at @jayprasuhn.

Discuss This Article