We know it matters for downhill racing but what about XC?

Check out this informative and genuinely surprising video from Specialized where they put various riding positions through wind tunnel testing.

>>> 6 ways to make your bike lighter

Kudos to Spesh for keeping the whole video to just four minutes long and getting to the point.

Unlike our road cycling companions, aerodynamics are not often at the forefront of our mind when mountain biking.

The last time the industry in general talked about them was during the infamous skinsuits-in-Downhill debacle where the UCI banned skinsuits for what was essentially a fashion and marketing reason. Skinsuits were significantly faster in World Cup downhill racing.

But what about non-downhill racing? What about at the other end of mountain bike racing, XC and marathon racing?

The Specialized wind tunnellers put a Specialized Epic in the tunnel and tested four different riding positions.

Positions tested

  1. Normal, upright, ‘baseline’ position. Hands on the grips, fingers covering the brake levers.
  2. Crouch. Hands as above but body hunched over, chin-on-stem stylee.
  3. Fork crown holding. Yep, that crazy hands-below-headtube thing that some World Cup XC racers do.
  4. Narrow, tucked in. Hands on bars directly either side of the stem clamp.

The test was based around the 100-mile long Leadville 100 endurance race. As such, the testers used last year’s winner’s (Howard Grotts) average speed as the wind speed test ie. 26 km/ph.

The results

Here’s how much time each aero riding position would have saved during last year’s Leadville 100, where the winning time was 6hr 15mins.

  • Crouch position = 17 minutes saved
  • Fork crown hold position = 21 minutes saved
  • Narrow tuck position = 23 minutes save

There you go, next time you want to make some significant* aero savings go for the narrow tuck hands-against-stem-clamp position. well, that’s if it’s safe to do so anyway!

*significant in a race scenario, it’s probably not worth doing it on your Sunday social ride.