The Borealis engineers designed the FF1 fork to match the superior rideability of the Borealis Yampa. We started with a 15mm thru axle—the first ever on a fat bike. While we did focus on reducing weight in the design process, lateral stiffness was the main priority. To optimize stiffness and handling ability, we paired the 15mm thru axle with a tapered steer tube that leads into massive, triangular-shaped fork legs designed with all of carbon’s strengths in mind: stiffness, light weight, and superior tube shapes. At only 575 grams, the FF1 is the lightest fat bike fork around.