Fat bikes project an image of being big, heavy, lumbering beasts of burden whose sole purpose is to dutifully carry you across the frozen tundra – slowly.
The Borealis Echo carbon fat bike hardtail, however, is sleek, efficient, nimble-handling, light, and anything but slow. Swap out the stock wheelset for something more befitting the rest of the package and you've got a seriously entertaining all-conditions machine.
Ride and handling: fast, fun, and flickable
Wait, did we really just describe a fat bike as "fast, fun, and flickable"? Indeed we did, and those words absolutely apply to the Echo.
Although there's no getting around the considerable rotating mass beneath you, the Echo's beautiful carbon frame is remarkably stout and efficient with no noticeable flex when you hit the gas. Couple that with the extra traction that comes with meaty 4in-wide tyres at ultra-low pressure plus the bike's comparatively low weight – just 13.07kg (28.81lb) for our complete medium tester without pedals – and you've got a reliable formula for cleaning technical climbs. If you've ever watched YouTube videos of Jeeps performing impossible feats of rock crawling, that'll give you a good idea of the Echo.
Fun? You betcha
The Echo isn't just about creeping up techy ascents, though, and the inclusion of a 100mm-travel RockShox Bluto RCT3 fat bike suspension fork and Reverb Stealth dropper post give a good indication of what the bike is intended to do. We started testing well before the snow began to fall in Colorado and found the Echo plenty capable on regular trails with prodigious amounts of turning and braking grip coupled with a level of stability that constantly begs you to push harder.
Not surprisingly, the huge tyre volume also pays big dividends in terms of ride quality. Smaller rocks and roots are simply flattened, washboard may as well be paved over, and at least at lower speeds, there's a commanding sense of do-no-wrong composure and confidence. Bigger hits still come through – the Echo is a hardtail, after all – and given the right mix of conditions, all of that undamped tyre casing will literally bounce you offline but otherwise, you're basically riding a monster truck.
The RockShox Bluto fork helps immensely any time the ground is even remotely bumpy
Borealis claims that the Echo was purpose-built around the Bluto fork and to the company's credit, the bike feels impressively normal with few of the sluggish handling traits that often afflicted earlier fat bikes. Much like any other modern conventional trail rig, turn-in feels intuitive and natural, there's minimal auto-steer (at least at reasonable tyre pressures), high-speed stability is very good, and the spot-on riding position is equally suited to both wintertime and summertime riding.
About our only complaint was a rear end that seemed slightly long, which occasionally made it a little tougher to loft the front end or pivot around tight switchbacks but that only came to mind when we had time to think about it. More often than not, we were just too busy having fun on the Echo to care.
Frame: futureproof fatty
Fat bike technology is progressing rapidly but Borealis has infused a good amount of futureproofing into the Echo. Thru-axles are featured at both ends (including the latest 197mm-wide rear spacing), all of the internal routing is fully guided for easy maintenance, and the threaded bottom bracket shell is not only less prone to creaking than press-fit cups but still accepts the newest 30mm-diameter crankset axles from Race Face and others.
The internal cable routing is fully guided for easy servicing
Up front is a meaty 1 1/8-to-1 1/2in tapered head tube with integrated bearing seats to minimise the stack height, the down tube wears a thick rubber guard to ward off rock strikes, and there's enough tyre clearance to swallow the biggest 4.8in tyres and 100mm-wide rims.
Should your fat biking efforts include some more adventure-type riding, Borealis also equips the Echo with three bottle mounts, and the frame will accept a front derailleur if multiple chainrings are more your style.
There's more than enough clearance through the stays for the widest tyres and rims
Claimed weight for a medium frame is 1,370g.
Equipment: great drivetrain but wheels and brakes need work
Borealis supplied BikeRadarwith its spare-no-expense flagship model – including a SRAM XX1 single-chainring transmission, ultralight Race Face Next SL carbon fibre cranks, an oversized 35mm-diameter Race Face carbon fibre handlebar and machined aluminium stem, and wheels from Borealis house brand Turnagain. It's a cracking spec sheet on paper, but on the trail there are some glaring deficiencies.
Shift performance from the XX1 transmission is flawless with reliable chain movement even under heavy pedalling efforts and in deep, heavy snow. Chain retention on the Race Face Narrow/Wide chainring is utterly reliable as well, and the carbon fibre arms are both incredibly light and impressively stout. Likewise, the oversized cockpit components are both surprisingly light and remarkably rigid.
The SRAM XX1 transmission was flawless
The same can't be said of the RockShox Bluto fork, however. It's generally a fine piece of kit for wintertime riding with a well-controlled stroke and very good tire clearance, plus we experienced no cold-related reliability issues even down to -13°C (8°F). However, there's noticeable twist below the fork crown from the 32mm-diameter upper tubes and comparatively spindly 15mm axle any time there's more abundant traction.
In contrast, we found the SRAM XX hydraulic disc brakes to work very well in milder conditions with good power (despite the relatively small 160mm-diameter rotors), excellent control, picture-perfect ergonomics, and bulletproof reliability over five months of regular testing. However, the pistons fail to fully retract when the thermometer drops well below freezing. In fairness, Borealis does normally equip the Echo XX1 with SRAM's newer Guide RSC brakes, which may well work better in such conditions.
The Avid XX brakes work well in milder temperatures but the pistons fail to fully retract when it gets really cold outside
The stock wheels are sorely disappointing in warm or dry conditions, though, and they're certainly not in keeping with the performance of the frame to which they're matched. The aluminium rims boast a pretty anodised finish, lightening holes, and durable stainless steel eyelets but a low-tech single-walled profile and crudely joined seams. The deep central channel not only makes them frustratingly difficult to set them up tubeless but hard to get tube-type tyres to seat evenly, period – not unlike cheap chromed steel department store 10-speed wheels of yesteryear.
The house-brand hubs leave much to be desired, too. Like the rims, they're unquestionably pretty to look at with their bright blue anodised finish and slick laser-etched graphics. However, the rear hub's 30-tooth ratchet ring offers up a slow 12-degree engagement speed while the front hub is apt is ditch its loosely held end caps into the surrounding snow when removing or installing the wheel.
The house-brand Turnagain FR80 rims look nice but their old-school single-wall profile leaves much to be desired
If you intend on riding the Echo primarily in snow, you'll want to trade out the stock 45NRTH Husker Du tyres as well. Their ramped, low-profile, and tightly spaced knobs roll quickly and grip well on harder surfaces but don't have enough bite for proper wintertime adventures.
Bottom line: fantastic at its core but rough around the edges
Borealis has earned an excellent reputation for producing top-shelf fat bikes and the Echo only further reinforces that notion with its rock-solid chassis rigidity, excellent handling, and thoroughly up-to-date feature set. The complete (and very expensive) XX1 build spends money where there's only marginal benefit and not enough where it really matters, though, and the so-so wheels unfortunately hold back what would otherwise be a genuinely fantastic all-seasons machine.
For more information, visit www.borealisbikes.com.
Complete bike specifications
- Frame: Borealis Echo
- Fork: RockShox Bluto RCT3, 100mm travel
- Headset: Cane Creek 40 integrated, 1 1/8-to-1 1/2in tapered
- Stem: Race Face Atlas 35
- Handlebar: Race Face Next 35 10mm rise
- Front brake: SRAM XX w/ 160mm rotor
- Rear brake: SRAM XX w/ 160mm rotor
- Brake levers: SRAM XX
- Rear derailleur: SRAM XX1
- Shift lever: SRAM XX1
- Cassette: SRAM XG-1199, 10-42T
- Chain: SRAM PC-XX1
- Crankset: Race Face Next SL, 32T
- Bottom bracket: Race Face Cinch
- Pedals: n/a
- Rims: Turnagain FR80
- Hubs: Turnagain FH150
- Spokes: Wheelsmith 14/15g double butted stainless steel
- Front tyre: 45NRTH Husker Du 120tpi, 26 x 4.0in
- Rear tyre: 45NRTH Husker Du 120tpi, 26 x 4.0in
- Saddle: WTB Pure V Pro
- Grips: Lizard Skins Peaty lock-on
- Seatpost: RockShox Reverb Stealth