Borealis Bikes

Yampa X0/X9 Complete Bike

This is what fat bike enthusiasts the world over have been waiting for. The team at Borealis drew from years of experience at the bleeding edge of fat bike development with the express purpose of making the Yampa X0/X9 complete bike the best possible tool for the job. You see, these guys have been riding fat bikes since it involved welding together pairs of standard width rims, so they've seen fat bikes develop from their infancy. Borealis adopted new standards for components and construction in hopes that it could deliver a product that improved on the competition in every measurable way. With builds coming in well under 30 pounds, we'd have to say that they've hit their mark. And it's not just the light weight that makes the Yampa so drool-worthy. With its proven SRAM drivetrain and Surly rims and tires, it's downright bulletproof too. If you view your fat bike as essential, and not a mere novelty, consider this your dream ride.

Borealis built the Yampa frame using the most up to date carbon fiber construction methods. Beyond shedding grams, the composite construction has enabled Borealis to finely tune the flex and build a strong frame that will hold up to year 'round use. The profiling of the seatstays in particular enables added vertical compliance, while the oversized chainstays keep the pedaling responsive when you stomp on the gas. Tire clearance was paramount, and accordingly, the Yampa clears massive 4.8 inch tires on a 100mm wide rim. To achieve that degree of clearance without resorting to a weaker offset wheel, the Yampa uses a Borealis 197mm spaced rear hub. The result is a dishless rear wheel, perfect drivetrain alignment with the 100mm threaded bottom bracket shell, and more than enough clearance for the drivetrain regardless of your tire choice. Naturally, there's plenty of extra clearance for mud, snow, or anything else you're likely to find yourself riding through. The head tube is a tapered affair, which yields incredible stiffness when paired with Borealis's thru-axle equipped carbon fiber fork. It's equipped with three bottle cage mounts, to keep you hydrated for long hours in the saddle. And at 1270 grams for a medium frame, this just may be the lightest fat bike frame in existence.

SRAM's X9 drivetrain got the nod for the Yampa's build, and it's capped off with an X0 rear derailleur. The crankset is a Race Face Ride setup, with 22/36t double chainrings for a wide gearing range. SRAM's BB7 mechanical disc brakes brakes handle stopping duties, and the cockpit is primarily Truvative hardware with a WTB saddle. The wheels are Borealis's own hubset, featuring a 197mm thru rear and a 135mm 15 QR thru-axle front hub. They're laced with stainless spokes to Surly Turnagain rims, wrapped in 3.8 inch Surly Knards tires. Think of it as a no-worries setup for extended adventures.

The Borealis Yampa X0/X9 complete bike is available in four sizes, from small to extra-large, and in the colors Black/white, and Black/red.

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