Borealis Echo Fat Bike

Traction on dirt is so good it takes some getting used to.​

The Lowdown: Borealis Echo SRAM X01 Fat Bike

While on the surface this is a straight forward bike review, it's impossible not to also delve into the question of whether fat biking is truly viable segment of the mountain bike world. Until taking delivery of the Borealis Echo test bike, I had all of two fat bike rides on my career cycling resume. I loved them both, but it wasn't entirely evident at the time what a beast this whole big wheeled business was going to become. It still had that niche-of-niche feel.

Flash forward to the present, and it's clear at least from an industry standpoint that fat biking is not just a pastime for snowbound Minnesotans. Many of the big boy manufacturers got into the game this past year, and we fully expect that trend to continue with more fat bikes and fat bike specific components streaming into the marketplace in 2015 and beyond.

But does that mean you should run out and buy one? My answer, after spending about two months tooling around on the Borealis Echo, is I certainly want one. They're truly a ton of fun - and based on my test time, not limited to bombing around in blizzards. I'm no Gee Atherton (or even Rachel Atherton), but I can go downhill okay on my 160mm-travel trail bike. Yet I managed to PR a couple descents on the Echo, which is testament both to the bike's nimble handling (yes, I said nimble), and the ridiculous amount of traction delivered by 4.8" tires pumped to 9 psi. It almost feels like cheating.

Of course, at $5,100 the Echo is also draped with lots of high-zoot parts (and a few not-so-hot ones), which you can read about in the full review below. But before you do that, check out this video from the folks at Borealis. If you thought fat bikes were only for snow and sand, they encourage you to think again.

Tire clearance: Up to 4.8" on 100mm rimWheels: Turnagain FR80
Drivetrain: SRAM X01 1x11Hubs: Borealis FH150
Cranks: RaceFace Turbine 32tBottom Bracket: Threaded 100mm shell
Suspension: RockShox Bluto RL 100mmTires: Surly Bud/Lou 4.8 120tpi
Brakes: SRAM Guide RS hydraulicRouting: Internal cables/internal dropper post
Bars: RaceFace Turbine 35mmCargo: Three bottle cage mounts
Stem: RaceFace AtlasWeight: 31 pounds (size L as tested)
Headtube: 1 1/8-to-1½ taperedMSRP: $5,100 (stock XO1 build)
Seatpost: RaceFace TurbineRating:
4 Flamin' Chili Peppers
4 Chilies-out-of-5
Saddle: Ergon SME30 Pro
Stat Box


  • Huge smile factor
  • Heavy wheels
  • Lightweight frame
  • Heavy tires
  • Nimble handling (seriously)
  • Heavy tubes
  • Great brakes
  • Not tubeless
  • Reliable 1x shifting
  • Auto-steer at lower pressure
  • Reliable chain retention
  • Bombproof cockpit
  • Massive tire clearance
  • Short chainstays
  • Convertible to 29+
  • All season versatility
  • Traction, traction, traction
  • Stability at speed
  • Fully guided internal routing
  • Stiff efficient frame
  • Climbs like panzer tank
  • Smoothes out trail chatter
  • Internal dropper post compatible

Full Review: Borealis Echo SRAM XO1 Fat Bike

As anyone who's spent time in the Boulder, Colorado area knows, it's a wonderful place - unless you like doing quality mountain bike rides out your front door. Indeed, though the area is blessed with hundreds of acres of scenic public open space, most of it is off-limits to bikes. In the battle for trail access, the angry hikers won.

Borealis Echo Fat Bike

The advent of the fat bike means days like these aren't reserved for skis -- or staying indoors.​

The trails that do allow bikes are mostly family-friendly fare, posing little challenge for anything beyond a hardtail (or even a 'cross bike). But what they do provide is a test lab for human interaction. Boulder's trails are busy, which often means the old stink-eye showdown between walkers and riders. Funny thing, though. When out on a fat bike, those frowns turn upside down. Apparently people love fat things, even though I could go just as fast or faster on the Echo compared to my other bikes, and if we did get tangled up in a blind corner, this 31-pound rig of rolling thunder would do a heck of a lot more damage than my 16-pound 'crosser.

That brings us to the Echo itself, which Borealis claims to be the first fat bike designed specifically around the RockShox Bluto, a 100mm fork that first came to life just a few miles from Borealis HQ in Colorado Springs.

"Honestly we probably didn't any more advantage than any of the other manufacturers, but [RockShox engineers] did come to our office a lot and, say 'let's ride,'" explained Borealis CEO Steve Kaczmarek. "Our buildings are maybe four miles apart. That's why we are almost exclusive on SRAM."

Continue to page 2 for more on the Borealis Echo and full photo gallery »

Borealis Echo Fat Bike

MSRP: $5,100 for this SRAM XO1 build. Borealis also offers $4,000 and $6,000 builds, or you can get frame for $1,950 or frame and fork for $2,650.​

Indeed, our test rig was outfitted with a SRAM XO1 1x11 drivetrain paired with a RaceFace Turbine 32t crankset. Braking was supplied by SRAM Guide RS hydraulics. In all cases the kit worked flawlessly. No chain drops, smooth shifting, and plenty of stopping power, which is especially important on one of these bikes.

For my money, a single ring drivetrain is the way to go on fat bikes (and most mountain bikes). All the extra big tire/low pressure traction helps you claw up things that heretofore might have necessitated a true bailout gear. And the Guide brakes deliver great modulation and stopping power, helping erase the memory of the company's former stoppers, which didn't always stop.

Other notable Echo highlights are the girth of the tires (Surly Bud (F) and Surly Lou (R) 4.8s), and more importantly the massive amount of tire clearance. Even with rubber that wide, there is still room to spare, meaning if you wanted a slightly lighter and more nimble ride for warm-weather use, you can swap on a set of 29+ wheels with 3.0 tires without clearance issues.

"Our strategy was to build a bike that could be an all-year bike with a quiver of wheelsets, which is a lot cheaper than buying a bunch of bikes," explained Kaczmarek. "Yes, that will change the Q factor because of the clearance for the wider set-up, but we still think it's a viable option."

Borealis Echo Fat Bike

Even with 4.8 tires there was still a little room to spare.​

We didn't get to experience the Echo in its 29+ form, but can certainly vouch for its playfulness with the burly 26-inch wide wheel set up. Yes, it's been a long time since I'd been on either a hardtail or a 26er, but the Echo really did feel flickable when playing on dry trail. That's due in large part to the full carbon fiber frame's design, highlighted by a head angle that's been suspension corrected, a shortened top tube, and 18.1-inch chainstays.

"Go back just a few years and most fat bikes were basically designed to get from A to B and not much else," explained Kaczmarek. "Like some of the other new fat bikes on the market, we shortened our chainstays so you're getting something that more closely resembles standard mountain bike geometry. And with that you get a more snappy, agile ride."

For comparison sake, Specialized's Fat Boy Pro with Bluto fork has chainstays that are 5mm shorter, while a traditional Trek Superfly hardtail is in the 17.5-inch range, with 29-inch wheels of course. Bottom line, it was surprising just how snappy the Echo felt.

Also surprising was that a 26-inch hardtail with a full carbon frame, no dropper post, and a 1x drivetrain could still weigh 31 pounds - even if it was a fat bike. Of course it's the wheels and tires that are of issue here. The bike was not set up tubeless, which means you hauling around a pound and a half of tube weight.

Borealis Echo Fat Bike

The cockpit is a RaceFace Turbine 35mm held in place by a RaceFace Atlas stem.​

The tires and wheels are no flyweights either, and at this price point we'd like to see a little more bang for buck than what you get from the house brand alloy Turnagain wheels and Borealis hubs. The wheels' deep channel make them tough to set-up tubeless, and the hubs don't engage particularly quickly. Tubeless compatible carbon rims are clearly the way to go, and we'd be surprised if they're not part of the Borealis product offering when the next model year bikes are launched.

Out on the trail (dirt or snow), all those thoughts were fleeting and far away. Mostly I just had a really good time, even if it took awhile to sort out ideal tire pressure. As any fat bike veteran knows, dialing in proper psi is not a set-it-and-forget-it proposition. On dirt, the Echo was best in the 8-9 psi range. That provided enough traction that you didn't need a running start to ascend techy spots, but could still rail descents without having the tires fold. Stability was train-track solid, and cornering traction was so good it took a little getting used to. Initially the brain simply doesn't trust what the bike can do.

Riding snow is a little trickier. You have to find the balance between maintaining uphill traction (less psi = better grip), and not getting too squirmy on descents (less psi = great chance of auto steer). I learned that later point the hard way during one winter-conditions session when after dropping the pressure just below 5psi, the bike drifted left, rolling off the packed down section of trail and into the soft stuff. The predictable result was rapid pilot ejection. Good thing the stick buried just under only stabbed a little ways into my left knee.

Borealis Echo Fat Bike

It may be a hardtail, but this bike can carve up descents with the best of them.​

Bottom line, make sure to carry a pump and ideally a small pressure gauge, too, and don't be afraid to experiment. Or even make changes based on changing snow conditions, or the simple fact that you'll be heading uphill or downhill for a while.

As for the final word on the Echo, we give that to Kaczmarek simply because we couldn't have said it better ourselves. "We understand that everyone wont be able to afford one of our bikes," he said. "But before you make up your mind about fat bikes, make sure you get on one of the newer lighter bikes. Don't just ride a heavy one, say this sucks and move on, because you'll be missing out."

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