TECH TALK with Matthew Sterbenz

By Matthew Sterbenz 4FRNT Skis

There’s nothing quite like a ski or board wall at a shop. To the untrained eye, the equipment might appear the same, but the truth is, the “wall” is actually organized by brand or category and selected specifically for the abundant local terrain at your fingertips. This column is dedicated to the daunting task of selecting the right setup for you this season.

The topic of geometry and how to select the right shape for your ski or riding style can be broken into three general measurements: width, sidecut and length.

Width

Width is typically measured at three points: Tip, waist and tail. The result of these measurements highlight the amount of taper the ski or board may have which translates to how the ski tip will feel when adjusting to different snow conditions.

If a ski has minimal taper, resulting in a more centered binding-mount position, the width dimensions of the tips and tails will be nearly the same. This is a shape most commonly found in terrain park skis, where riding switch is common.

If the measurements show a wider margin between tip and tail, the result is that the ski or board tends to be more directional and thus less versatile for switch use, but better in variable snow conditions. Skis with greater width margins in the tip and tail tend to dictate a mount position further fore or rear of center.

Key point here: Realize your desired mount position and then seek out the dimensions that naturally accommodate you.

Sidecut

Every ski or board is the product of multiple circles, or radii.

Sidecut, a visual term, references how much width is removed from the waist, or center of the ski or board. It gives the boards that “hourglass” shape. A ski with a lot of sidecut will have a short “turn radius.” Turn radius is the scientific measurement of how quickly or slowly a ski or board will turn across the fall line, and is the factor that determines whether you want to make big or small turns.

So, if you desire a lively feel with short turns at moderate speeds, or you ride in mostly terrain parks, you should seek out a deeper sidecut.

The opposite would be a shape with less sidecut, resulting in a longer turn radius. If you’re a tram guy and turn only when necessary, then finding a ski or board with less sidecut will result in a considerably more stable feel.

Length

Most freeride skis and all snowboards have turned up tails. The versatility of this design influences your choice in length.

A sizing rule for a skier looking to grow with a ski is to find a setup that stands between your nose and head height. Likewise, when hunting down a new snowboard, the usual reference is between your chin and nose. The length of traditionally shaped skis – those without turned up tails – can be measured like a snowboard, between your chin and nose, given the skis’ on-snow running surface continues throughout the ski.

Also take into consideration how long a radius is used to create the ramp between your tip and tail. For powder skis or boards, the tip or tail is more drawn out than that of a shape designed for riding groomers. To do this, you’ll want to check out the shape of the side profile. Sight down one edge and get a sense for how much will actually be contributing to the running surface and how much will be simply there to support the float of the tip and tail.

One 158 cm board versus another of the same length may have drastically different results; similarly, a ski in 171 cm and 177 cm could be nearly identical in actual running surface once you realize the variety in tip or tail radii.

Matt is a former freeskiing professional who now spends his weekdays running 4FRNT, the ski company he and his friends started 10 years ago. 4FRNT is based out of Salt Lake City and calls Alta its home resort. You can find 4FRNT locally at Gallatin Alpine Sports, or online at 4FRNT.com.