An inside look at Gerard Karpik’s snowmobile air shock technology

There’s a mad scientist hard at work in a dusty, dimly lit armory-turned-snowmobile-engineering-shop in the blue-collar town of Eveleth, Minnesota. He’s not refining a sinister plan to rule the world. Instead, this guy is passionately pursuing better suspension performance from snowmobiles.

This silver-haired, cross-country racing legend from the heart of northern Minnesota’s Iron Range is a snowmobile suspension pioneer who’s worked hard to improve ride quality and control since his days racing Ski-Doos, Alouettes and Sno Jets in the 1970s and ’80s. Racing was followed by some time designing suspension systems for Ski-Doo in the 1980s, and then founding FAST Inc., the company that created the M-10 rear suspension and Blade snowmobiles.

Surrounded by high-tech machinery that’s guided by CNC programming, welding equipment and a small staff of other “rangers” who seems equally excited about suspension technology, 56-year-old Gerard Karpik grows a snow-eating grin on his face when he talks about sleds. Ask him about the new Tri-Tek Airshock system and this engineer gets an especially wide, kid-like twinkle in his eyes.

A Simpler Design
We visited “King” Karpik — a nickname earned during his storied racing career — at his company headquarters (now called TeamFAST) to learn about his newest way to improve ride quality.

Tri-Tek is a three-shock system developed for the front two-thirds of rider-forward sleds. It includes a pair of Assault Airshocks over the skis and another Airshock for the front torque arm. Assault shocks are an emulsion design, meaning the oil and nitrogen are mixed. This is a simple design that is more durable than internal floating piston (IFP) shocks used on most modern snowmobiles, Karpik said. Early gas shocks were emulsions, but sled manufacturers switched to IFPs by the mid-1990s.

Air shocks have become mainstream on snowmobiles since being introduced by Fox in 2004. But TeamFAST’s design is different because the air chamber on Assault Airshocks is a flexible, rolling membrane rather than a rigid metal cavity. Karpik debuted this shock technology in 2007 as an upgrade to his company’s Air-Wave and M-10 skidframes. This membrane has more than twice the air capacity, on average, than FLOAT or RydeFX Air 2.0 dampers, according to calculations from Karpik.

More air spring volume provides a less progressive spring rate through its stroke so air pressure doesn’t increase as quickly upon compression. For example, when inflating a regulation size basketball used in the NBA and a smaller junior league ball to 50 psi each, the little ball will rebound faster and higher if dropped from an equal distance from the ground because its air is housed in a smaller area. The same principle applies to shock absorbers; more air volume under the same pressure translates to a softer, suppler feel.

Another reason Karpik said he uses a rubber air spring is because it “rolls up” into itself as it’s compressed, allowing for a smoother operation than competitive designs that suffer from friction between the air sleeve’s seal and shock body. Air pressure in Karpik’s shock is adjustable with an external, hand-held pump.

300 Miles In A Day? No Problem
Tri-Tek is a departure from TeamFAST’s traditional business model where it sold complete M-10 rear suspensions that had to be retro-fitted with careful measurements, precise drilling, and then bolting and riveting the mount kit to the tunnel. But installing this setup is as simple as tightening six bolts.

Gerard Karpik has made a living developing suspension technology in a part of Minnesota where most other people crack rocks in iron ore mines.
Karpik said Tri-Tek is designed for anyone who’s tired of getting beat up by their stock suspension, high-mile tourers and “guys who brag about riding 250 to 300 miles in a day.” The system has a lot of flexibility, he said, so it can handle the rugged damping duties required for a cross-country race sled, too.

Packages are available for Ski-Doo REV and REV-XP models; Yamaha Nytro, RX-1 and Apex; and Polaris IQ-based sleds. The Tri-Tek kit sells for $1,090.’

Learn about more new suspension technology from TeamFAST at!
Go to and look in the Video Gallery for TeamFAST Tri-Tek to see more photos and watch exclusive video from our trip to, including information about the company’s Dive-Tek system.

Leave a Reply

Your email address will not be published. Required fields are marked *