The Juliana Roubion Mixed-Wheel Mountain Bike Eats Plungy Roots and Rock Gardens for Breakfast

The Juliana Roubion is a highly capable mountain bike that descends confidently and can climb back to the top for more laps.
All photos by Molly Cameron

Reviewing the solidly enduro-focused Juliana Roubion mixed wheel mountain bike is a tough task when all I want to say is ‘buy it and you’ll be stoked.’ With 160mm of travel in the front and 150mm in the rear, this bike is a rip, and after dozens of test rides covering significantly diverse terrain, I’m happy to report that the high-performance bar set long ago by Juliana and their sister company, Santa Cruz, remains solidly in place. 

I tested the bike in as many places as I possibly could throughout western Oregon and Washington; on singletrack adventure loops, lift-accessed parks, loamy and rooty Bellingham duff, as well as the dry volcanic soil of the high desert. While the 2022 Roubion performs well on just about all surfaces, it really shines when the going gets steep, loose, and spicy.

There are two standout features of the 2022 Roubion that I found truly shout-worthy. One: the adjustable geometry made possible via flip chip, and two: the “business in the front and party in the back” mixed wheel set. While the flip chip has been available for some time, pairing it with the mixed wheel set really helps the already capable Juliana Roubion shine even brighter than the earlier models. I appreciate the confidence and stability provided by the large 29″ front wheel and found equal enjoyment in the nimble cornering capabilities afforded with the 27.5″ rear. This was my second experience with a mixed wheel bike, and I think Juliana nailed it. This truly is a best of both worlds situation. I found the bike to be smooth, stable, and well-balanced through both tight switchbacks and gentle berms. Throw in the extended geometry offered by the flip-chip, and it’s hard to imagine a better quiver killer for the gravity obsessed than the new Roubion. 

The trail tale

So how does it ride? Like a bison charging down a hill, or maybe like a bison with the grace of a Cirque du Soleil acrobat. It eats plungy roots and hole-full rock gardens for breakfast and still has enough appetite left for whatever flowy berms, air-loving park features, or gnarly singletrack you point it at for the rest of the day. If I had to choose, I’d rather ride this bike up singletrack than a fire road. The bike’s pedal bob was a minor irritant, and I didn’t notice it much on the trails. I think Juliana has perfected the balance with their head tube and seat tube angles, to maximize the fun going down and minimize the struggle going up. At 30lb, the Roubion is not lightweight, but I found myself forgetting about weight on the climbs and enjoying my ride buddies’ conversations and the surrounding forests. 

When I get to the bottom of a run, I like to contemplate how often my mind was distracted by something particular about the bike while descending; when I preload on the lip of a jump, does it respond just right? When I’m rounding a corner, do I feel balanced in my body or am I adjusting to compensate for the bike? How does it respond if I have to grab a handful of brake at the last minute? More often than not, I would get to the bottom of a trail and realize that I didn’t even notice the bike. I can’t imagine a better marker for a great mountain bike than one that just gets out of your way and maximizes the smiles and fun!

Who this bike might not be for?

The Roubion is not the most playful bike I’ve ever thrown a leg over. Compared to my regular ride, a balanced 27.5″ Ibis Mojo HD5, the Roubion feels a bit more grounded and less interested in poppy play or gleeful bounding. It’s more of a staid and steady draft horse. The bike is exceedingly capable of going fast and charging down whatever you want to point it at, but if you’re looking for lighthearted zing or winning a race full of sprint-heavy power climbs, this might not be your whip. 

Anyone with a love for gravity-inclined dirt shredding and a medium tolerance for climbing will dig this bike. Obviously, this isn’t a light XC or trail machine, but it’s not a complete slug on the climbs. In the fully-slacked geo position, you might not be the first person in your crew to the top of the climb, but you’ll enjoy the way it rolls blissfully over any technical momentum blockers you encounter on the way to the summit. I pedaled the Roubion for a consistent 2+ hours to reach a local descent and never once lamented the weight or geometry, and I was so grateful to have it on the way down! 

This bike will suit nearly every level of rider from beginner to professional enduro racer. During one session on the Roubion, I had the pleasure of riding with the young enduro phenom-in-training, Penelope (the daughter of Singletracks Editor, Gerow). At one point we decided to switch bikes while riding at the Mt. Bachelor bike park. I hopped on her full suspension XC Liv Lust and she took (what I thought would be) one lap on the Juliana. The shift in her speed, confidence, and smile wideness was immediate. Needless to say, she did not offer to switch back until the last lift run of the day. 

Frame details

In the high flip chip position, the Roubion is a joyful romp in the woods, or the desert, or wherever you find yourself riding; climbing and descending, this position will carry you through a large swath of terrain. I tested the bike in the high position for several weeks before swapping for the low and I never found myself wanting more until of course, I flipped that chip. For those who prefer their trail spiciness levels more on the fiery side of the spectrum, trust me on this one, you’re going to want to move the chip to the all-slack-and-low position. Juliana is not kidding when they say this is two bikes in one. During a particularly hero-dirt-filled weekend at Mt Bachelor bike park, I spent day one riding all day with the geo in normal mode, then flipped that magic chip and spent day two in would-not-shut-up-about-how-amazing-my-ride-is mode. When riding the Roubion in slackAF mode, this bike turns into a legit sled! If you like to process your emotions out loud as I do you might tell your friends they will just have to put up with your exuberance for the first few rides or ride faster. Alternatively, they could also buy a Roubion.

On to those mixed wheels, Juliana’s marketing folks claim that the “Roubion’s MX wheel combo feels like the best mix since Aperol met spritz.” As a former resident of Aperol’s birthplace, northern Italy, I feel compelled to point out that the proper exclamation would have been to say that it is the “best mix since Aperol met Prosecco,” since “spritz” simply means a “splash” of water. I’ll forgive the technical impasse because the statement is both clever and accurate, at least in spirit. If I had to write the marketing copy, I might have said that the 29/27.5″ wheels are one of my favorite combos since Miles Davis met John Coltrane. Each build spec comes with different rim and hub options so I recommend viewing Juliana’s spec page for details. The stock tires on all the builds are the Maxxis Minion DHF 29″x2.5, 3C, Maxx- Grip, EXO, TR. The 2.5-inch width felt plenty wide for all the terrain I encountered and offered ample frame clearance, with room for mud.

The frame comes in the C or CC carbon layups with fully internal cable routing, a threaded bottom bracket, and space for a water bottle inside the front triangle — even on the extra small. The underside of the rear triangle tubes and top of the chainstay are covered with integrated frame protection. The matte Blue Steel and Purple paint is absolutely gorgeous, but it does scuff easily. After a couple of tumbles, there were visible marks on the paint I wasn’t able to rub off. If you care about keeping your rig looking factory floor pristine, I recommend a frame protection kit. 

Geometry

The flip-chip is tucked in tight.

The geometry is slightly different across the sizes and varies with the low and high position of the flip chip so be sure to check out Juliana’s website for specifics. I measure at a generous 158cm (5’2″) tall and I tested the size small. I have often flirted with the 29er wheel size in my mind, but at my height, I’ve always been too timid to commit, worried about how low the saddle could actually drop, how deep inside the frame I would sit, or whether I could actually touch the ground when I need to dab on a sketchy turn. I was delighted to find myself fitting quite well on the bike and the Reverb 125mm dropper post gets that saddle well out of the way.

In the high chip position, the head tube angle is 64.7°, regardless of size; in the low position it slacks out to 64.5 deg. On the small bike, the seat tube angle flips from 77.2° to 76.7°. I was amazed by how such small angle changes could impact the way the bike rides. Depending on your riding style you may find more joy in one over the other; when the going gets steep, I found myself completely in love with the low position. The Roubion became a bit more soggy feeling while climbing, but still quite manageable. If I were to race this bike and was certain there were zero climbs on course, I would choose the low position. But if the tracks demanded significant pedaling or sprints, I would set it in the high position.

Suspension

The X01 AXS model tested here comes with the Fox 36 Float Factory 160mm fork and the RockShox Super Deluxe Ultimate shock. I can’t say enough positive things about the fork, with the GRIP2 damper and FLOAT EVOL air spring. The fork doesn’t have any climb or trail settings; just adjust the pressure and dial in all your settings and smash it through whatever trail you can throw at it. I found the factory-recommended pressure setting worked quite well for my 63.5kg (140lb) weight.

Admittedly, I prefer Fox over RockShox, and this preference bore out on the Roubion rear suspension. I found the RockShox to feel a bit sluggish. I was never able to get the rebound and air pressure combination dialed exactly to my liking. It always felt like the rebound was slower than I wanted until it was way too fast and I aired it up well over the recommended pressure, and still the shock felt too soft. I tend to like a poppier rear suspension, and I struggled to get the front and rear even. In the climb position with significant air pressure there was noticeable pedal bob. While this might not trouble some riders, as a recovering XC racer, I want to feel most of my power going into the climb, not the suspension. Regardless, it didn’t get in the way of my enjoyment once I pointed the bike downhill.

Component spec

This was my first ride on electronic shifting, and the SRAM X01 Eagle AXS provided me with a wonderful to the brave new world of cable-less electronic shifting. Aesthetically, the clean cockpit is certainly a win, and functionally, I enjoyed the ease of moving through the gears with the slight twitch of the thumb. My fears of possibly running out of battery on a long ride were never realized. In fact, I failed to find the measurable limit of the battery life. In the two-month test period, I only charged the battery once, out of concern of not knowing how long it would last, not because I ran out of power. My understanding is the more you shift, the more you drain, so if you’re doing several back-to-back all-mountain tours, you may find yourself needing to recharge more often. Back-to-back shuttle days will leave you with weeks of battery life.

The stopping power of the SRAM Code RSC four-piston brakes is notable, particularly when paired with the 200mm rotor up front and 180mm in the rear. I would, however, like to see a 200mm rotor in the rear. I’m not certain why they chose to go smaller there, and having a top-of-the-line Shimano option for this build would have also been ideal.

I was pleased with all the touchpoints and didn’t find myself wanting to swap out the saddle. I’m rather particular about my saddles, but the Juliana Primiero and my backend seemed to get along just fine, even on the longer days with significantly more pedaling than coasting. 

It was a sad day when I had to ship the Roubion back to its California home, and I would love to have kept it for another month or twelve. When I’m lining up options to replace my current ride, a Juliana Roubion will certainly be in the running.

Party laps

  • Descends like a charging bison
  • Climbs well on singletrack
  • Mixed-wheel is perfect for shorter inseams

Pros and cons of the Juliana Roubion.

Dirt naps

  • Paint scratches easily
  • Flip-chip is difficult to access