Borealis Pres Release Photo

It seems like not all that long ago I was first hearing about fatbikes – bizarre creations with huge tires designed to go where no bikes had gone before. In no time at all, the fatbike arms race is on par with any other category of bikes with a rush to lighter, stronger, and faster bikes and the inevitable carbon fiber. Companies anywhere from tiny NAHBS type builders to fatbike giant Salsa have shown carbon fatbikes, so what is a new fatbike company to do? Jump right in with a carbon bike of their own, of course.

That is exactly what Borealis plans to do with their all new Yampa carbon fatbike which owes its name to the Yampa river in Colorado. The new company is the result of collaboration between Adam Miller and Steve Kaczmarek, with design help from Pete Basinger. Adam cut his fatbike teeth working for and 9:zero:7, while Pete has more than a bit of experience both with Fatback, and as a champion Iditabike racer. Combining their skills, the resulting Borealis Yampa enters the market as one of the lightest fatbikes around.

Due to the light weight of the Yampa, Adam points out that you are able to do more with a fatbike this light saying, “The frame and fork are currently the lightest on the market. We will offer complete stock builds under 25 pounds with standard fat bike configurations.” Essentially, it becomes more of an everyday mountain bike that isn’t tied down to a single season. Target frame weight for the Yampa is sub 1300g with the fork coming in at 580g. Compared to other fatbikes like the 9:zero:7, the Yampa has a longer top tube, shorter head tube, and about 5mm shorter chainstays which should improve its all around trail manners. Much like the Salsa Beargrease Carbon, the Yampa features a tapered 1.5-1 1/8″ tapered carbon fork with a QR15 front axle. Miller mentions that with the bigger 4.8 tires and 135mm front spacing the thru axle makes a world of difference in the handling of the bike. The fork will also be offered for aftermarket sale, with the company open to providing it to other frame builders for OEM builds.

The frame also features full rear rack mounts – something not that easy to employ on a carbon frame. Specifically, Adam states that Old Man Mountain racks fit perfectly on the Yampa.

Borealis Press Release Photo 3 - Copy

The rear axle remains a standard quick release, but it does bump up to a symmetrical 190mm – confirming the rumors of the new wider fatbike standard. Adam said that other companies may be going to the 190mm spacing as well which allows for 4.8″ tire clearance on 100mm rims with a 2×10 drivetrain. One big difference from the Beargrease is a 100mm threaded BB instead of a press fit unit. The Yampa will be front derailleur compatible with the aid of devices like Problem Solvers front derailleur adapter.

Cable routing is fully internal with shift cables jacketed internally for split housing, and brake hoses routed all the way through. After seeing that Borealis was offering an XX1 version on their site, we inquired what they would do for a crank since Salsa has the exclusive on OEM 100mm XX1 cranks for the first year of production. To get around the issue, XX1 bikes will be shipped with the most suitable crankset and a Wolf Tooth Component XX1 compatible ring.

Borealis Press Release Photo1

Complete bikes will be built with Borealis’ own 32H j-bend hubs which will also be sold aftermarket. Offered in red or black, the 190/135mm pair have a QR15 front hub with is convertible to a standard QR with a tool-less conversion cap system. The rear hub utilizes a 6 pawl engagement mechanism with the option for an XX1 driver.

Availability of the first Yampas is expected in August, with pricing set at $2,249 for a frame and fork, and complete builds starting with x.9/x.0 at $3,599. In addition to the complete builds, Borealis plans to offer custom builds in the future through their website allowing you to build your dream fatbike. Borealis is currently accepting preorders from individual or dealers.




  1. Sevo on

    I got a chance to ride it around today here in Colorado Springs. Pretty sick and pretty damn light. Be a great addition to our local cycling community here in Colorado Springs. We’ve got a few more cool start ups you’ll be hearing from soon 🙂

  2. Eric on

    Still trying to figure out the point. They seem cool for winter riding but there’s no way it’s faster than a 19lb hardtail.

  3. SmooveP on

    @Eric, the point (if there really has to be one) is the ability to roll over just about anything. The outer diameter of the tire is the same as a 29er and the extra width gets you over sand and other loose stuff. The low pressure (5-10psi) provides pretty decent suspension without the added weight or complexity. Traction and cornering is awesome. I’m 2 years into fatbiking and have not ridden in snow yet. I started out with a 40lb Pugsley and upgraded to a 27lb Ti from Twenty2 Cycles. I don’t ride my other bikes at all (and I own a bunch). Did I mentio that they’re fun as hell?

  4. Jeff on

    Eric, there is no point…unless you like having more fun on a bike than you’ve had in a really long time. Like you, I was once a skeptic, then I borrowed one for a day. Now all my high end squishy carbon and really aero road bikes just hang, and hang, and hang.

  5. Jeff on

    Almost 5K views in less than 24 hours……Yeah, Fatbikes kinda rule.

    Quick show of hands, how many folks reading this are already building it in their heads and debating about rim width and diameter’s? “Standard” Clown Shoe, versus the 47-50mm wide 29” Krampus rims with the 3.0 Knard’s maybe? This is gonna be fun to watch the next few years.

    Electronic shifting, and a suspension fork from a major manufacturer is on the way I’m sure, so do you wait on that? Or beat the Christmas rush and just piss off the wife?

  6. axle on

    Looks sweet! Fat bikes are so much fun. But I think Master Blaster may be right- a 650b fatbike would offer better flotation.

  7. Denny on

    Oh, great! One another hub spacing! WHy do they not stay with 170mm this I don’t know.

    I dont trust it will not break, better steel or even better TITANUM!!! 😀

  8. Jeff on

    Denny, 190 (or more) allows for more wheel/tire combinations without compromise. Clown shoes with BFL’s aren’t something I wish to run, but lots of folks do, and they want it on a high performance fatbike that doesn’t weigh 36lbs. Moonlanders can and do run that combo, but nobody is ever going to accuse a Moonlander of being a high performance or lightweight bike.

  9. craig on

    love the fat. ride it all winter, which is most of the year here in Alaska. but still don’t see the dirt appeal. finally on the 5-spot now. climbs better. way faster. way easier to carry on those real, no-trail-available (except maybe for that left by a moose) mountain explorations. still, i must admit it takes some adjustment switching back to 2.2 tires. there is a tank-like security to a fatbike. it feels like you could ride over anything. and they do offer some great beach-riding opportunities.

  10. randy on

    I could use one of these for building trails and packing it down…or for crushing the bushes to make an initial line.

  11. Kevin on

    I’m still very skeptical about these all-up claimed weights of 24 and 25lbs for carbon fatbikes. I worked out that my fat bike carries a 6lb weight penalty on the rims&tyres alone, and I have the lightest combo available – marge lites / 120tpi knards and tubeless using tape. This makes a 28lb beargrease equivalent to a 22lb fully rigid MTB, which is completely believable. With a carbon frame then even 26lb is believable (equiv to 20lb with normal tyres). But when you start talking about clown shoe rims and 4.8″ tyres you’re looking at an extra 1lb PER wheel (even assuming tubeless, which no stock fatbikes are). This means a 25lb borealis would weigh 17lb with ordinary rims and tyres….. Do you believe that ???

  12. Jeff on

    Kevin I am with ya on the weights. Whether it’s this bike, or the carbon Beargrease, there is no way the weights being floated about are accurate. Like yourself, I have a very high end fatbike with some pretty expensive stuff dripping off of it everywhere, and it’s still 31.5 lbs, granted that’s with a Thudbuster and a full pound of sealant between the two tires, but ever removing those two “extra’s”, I still don’t see where the extra 4-5 lbs is coming from. Plus, these bikes aren’t going to have XTR brakes like mine, or an ENVE bar. So remove those items and insert a cheaper (heavier) alternative, then throw on the Clown Shoes or BFL’s, and I only say that because this bike is being pictured with them… there is simply no way this is a 25lb bike.

    At any rate though, the weights are coming down and that’s a welcome thing, and I want this bike, really bad.

  13. SmooveP on

    My Twenty2 is a legit 27lbs with Marge Lites, Escalators, Hope hubs, White Bros fork, X0 2×9, and XTR pedals. I think I could squeeze another pound out of it, but it wouldn’t be cheap or easy. That all-carbon fork, like Carver’s, is probably worth a pound or at least a half. Tubeless is not necessarily lighter.

  14. AZBikeFreak on

    Who cares about another Fat bike? There is at least one Fatbike for sale on Craigslist every week.

    I love the pics of my old stomping grounds. Palmer Park in Colorado Springs. I miss those trails. Best urban mountain bike park in the country. It has everything from killer views to super tech climbs and bomber descents.

  15. BigJilmbo on

    Dude was absolutely sending it on those sweet jumps. I had no idea that fatbikes were such capable dirt jumpers. Sign me up! Waaay more rolling resistance, able to soar on 4 foot gaps, and the trail erosion capabilities of 4 bikes all in one. What more do you need?

  16. Brendan on

    For what it is worth, my salsa beargrease (Al from last year) is 25.6 lbs with 2,7″ DH tubes, Nate front, Escalator rear. It is set up 1x 10 with no chain guide (WTC chainring). These new carbon frame+fork are 1.5lbs less than what I have, so the weights posted are accurate. Also if the Dillingers come in at 1000-1100 grams like they are claiming (for this coming year), my bike will drop another 3/4 lb or so. Here is the bike before the WTC ring took off another .2 lbs or so.

    I expect my race fatty next year will be right in that 24 lb range or just under. That is pretty awesome given that my first stock Pug was 35lbs!

  17. Rick on

    If you don’t get it, don’t get one!
    But if you do get it, you will want more than one!
    And to the guy who ref’d to a ti fatbike – heck yes! my fatback ti w/ lefty fork and thudbuster seat post puts a smile on my face each ride – and makes each rider I see smile even bigger right back. And before someone starts railing on why i added stuff to a squishy fattire bike, let me say this: b/c I felt like it. just like I “feel” like riding my carbon 29’er f/s some days, my road bike others, my fat bike on others, etc. So come join the circus and get back to fun – I’m thinking of asking Strava to add a fatbike super slow category to balance out the folks who forget that for most of us, riding a banana seat cruiser w/ the shifter in the center is how we started our love affair w/ the sport.
    Peace and fatbike love!

  18. steve on

    listen to all you bike dorks spewing about weight and parts and if they are fun or not. Just shut the @#$% up and get on a cool new fat bike and have a blast riding where standard mt bikes cant go!!!!!Just shut up and ride with a smile! Isnt that what cycling is about?

  19. Gpb on

    Here’s why weigh is important – water weighs 6#to the gallon. You need a gallon or more to ride all day in the desert – actually anyplace where it is hot. So a 40 lb Moonlander + gear + Water = 50+ lbs of bike to pedal around, versus something like Borealas at 35. Big difference, particularily if you want to ride hot, arid conditions loke the SW or like me, the Empty quarter on the Arabian Penninsula.

    My only concern with the Borealus is the frame is way skinny, delicate even. It look like it will stand much compression loading from a big guy in the saddle droping down a few feet onto hard pan.

  20. Mark J on

    Purchased a Borealis Yampa, 2×10 X9-XO comps, Rolling Darryls, 45n Dillingers w tubes, Carbon bar, Atac Pedals, 27.5 lbs in an XL frame, if I go tubeless will shave another pound off…love the bike, haven’t had so much fun since I started Mtbing 15 years ago…

  21. Rob on

    Trek Farley 9.6, XL, Sram XX1 crank and cassette package, reverse pedals TI, HED rims tubless, whiskey carbon post, bars and stem 24.5lbs total weight


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