This article first appeared in the March 2022 issue of Adventure Cyclist magazine.
Mountain bikes have splintered into an almost comical number of ill-defined categories: all-mountain, cross-country, downhill, trail, enduro, downcountry, super-enduro, freeride, hardcore hardtail — the list goes on. Thankfully, the Kona Unit X thumbs its nose at any attempt to file it neatly into any of those categories.
The Unit is Kona’s long-running singlespeed model, and a few years ago it got a geared sibling, the Unit X. The 2020 frame update added more braze-ons, a switch to 29er wheels, and modern geometry that borrows from Kona’s Honzo trail hardtail.
The frame is Reynolds 520, which is chromoly steel produced to Reynolds’s specifications in Taiwan. There are three bottle mounts (including one under the down tube) and triple cargo mounts on each fork blade. Racks can be mounted front and rear, and there is plenty of room and mounts for fenders as well. If you look closely, there is still a cable stop for a front derailer if that kind of urge ever strikes. Sliding rear dropouts allow for some wheelbase adjustment or to convert to singlespeed after an errant rock takes off that rear derailer in the backcountry.
The geometry is thoroughly modern but not extreme. The 75° seat tube angle is a few degrees steeper than what was common a few years ago, but most riders will have no issues adapting. The stock seatpost has a bit of setback, effectively making the seat tube angle a little slacker. The 68° head angle might seem steep to the shredders out there, but the long reach and support from the rigid fork keep that front wheel out ahead of you on steep descents.
This 2022 Unit X has a 12-speed Shimano Deore drivetrain, a change from the previous SRAM SX. Shimano handles the braking as well with Deore MT410 hydraulic stoppers. WTB Ranger 2.6in. tires are an excellent all-around choice and sealed up nicely when set up tubeless on the WTB i30 rims. Kona didn’t skimp on the hubs, choosing adjustable and rebuildable Shimano hubs with thru-axles in Boost spacing.
Set up tubeless with a Bontrager dropper post, VP pedals, and a bit of mud, the Unit X weighs 31.2 pounds. You could throw money at this bike to make it lighter, but why bother? Everything here works, is plenty strong for hard use, and doesn’t cost an arm and a leg to maintain.
I spent a lot more time riding pavement with the Unit X than I had expected as wet weather often kept me off the trails. I was impressed at how well these big tires rolled on the road. Unlike some bigger 29er tires I’ve ridden, which can buzz annoyingly on pavement, the Rangers were quiet. Kona has an earned reputation for making fun bikes to ride off-road, and the Unit X carries this lineage forward. I was initially worried about the harder “Fast” compound of the Ranger tires, but even in some mud and snow, these tires delivered consistent and predictable traction and let go with plenty of warning. This seems almost like magic for something that rolls so well on the road. These 2.6in. tires are closer to most brands’ 2.8s in width, and I was able to run low pressure (18 psi front, 20 psi rear), which I’m sure helped.
While most mountain bikes are being built around steep seat angles for climbing steep inclines and then bombing back down, the Unit X can handle flat and rolling terrain better than many of the more hardcore hardtails out there. Why? Those steep seat angles that are in vogue really do work well to keep you over the pedals on steep ascents. But on flats, being high and forward over the pedals can be tiring and put more pressure on your hands. And standing to pedal can be hampered by the high and forward placement of the saddle. Kona nailed the middle ground with this bike, which is right where a rough-stuff bikepacking bike should be.
I installed a dropper post when I built the Unit X, and I’d recommend that to anyone who wants to ride it on technical trails. While I wouldn’t call this steel frame particularly forgiving, it certainly wasn’t harsh and never felt too flexy either. I think there is some magic to that rigid fork. Maybe it’s the tapered legs and straight steerer; the front end steered where I wanted it and never felt as harsh as I expected. The 44mm headtube means you can swap the rigid fork for a suspension fork with a tapered steerer, with a recommended travel of 100mm. Honestly, I would just leave it rigid; that much travel isn’t worth ruining the rigid goodness. If this was my main off-road ride, I would swap to a bigger front tire. There’s plenty of room for a 29 x 3.0in. up front, maybe 29 x 2.8in. in the rear.
I noticed, mainly on the road, the pretty large seat-to-handlebar drop. The headtubes on all sizes of the Unit X are on the short end. Combined with a short fork, the stack height is pretty low for a modern mountain bike. For comparison, a large Honzo has a 642mm stack, and the Unit X is 606mm. I’ve always found a lower bar helps with leverage when cranking on a singlespeed, but for gears and a not-23-year-old rider, I would like to see a higher stock bar height. If I kept this bike, I would swap to something like a high-rise Hunter Smooth Move bar and dial the fit in with the stem spacers. For what it’s worth, I never thought about the bars being too low when I lowered the dropper off-road.
I did notice one caveat to the otherwise excellent build kit: the headset is a bit of a turd. Hidden under that nice aluminum top cap are caged bearings with hard plastic seals. The plastic seals didn’t do much sealing, and the bearings needed to be tightened after or even during any off-road ride. Luckily, swapping in a proper headset is a pretty simple fix. One small quibble is that the dropper cable routing is on the wrong side of the down tube; running it on the driveside would create a more gentle loop of housing from the remote and prevent the cable from rubbing the headtube.
Most modern mountain bikes are marvels of modern tech, but all things that have made them more capable and comfortable also make them less versatile. The simple Unit X is the most direct descendent of the original mountain bikes that’s on the market today. It cuts through the hype and confusion to deliver a simple vehicle ready for almost any adventure, from mild to wild. With a few minor parts changes, it could be an all-weather commuter, a rigid ripper, a gravel slayer, or a bikepacking monster. But even the stock build can let you get after any and all of these things, right out of the box. To top that all off, the Unit X is a bargain and is available as a frameset for $699 if you want to roll your own.
The Unit X is a perfect gateway drug for new riders to experience all types of riding. For experienced riders, the Unit X can make old trails new again with the rigid experience or act as a blank canvas for a spectacular bikepacking build. Kona’s mix of modern geometry and classic functionality is the perfect recipe for adventure.
Sizes available: S, M, L, XL
Size tested: L
Weight: 29.9 lbs. (stock build, no pedals)
Head tube length: 130mm
Head tube angle: 68°
Seat tube length: 470mm
Seat tube angle: 75°
Top tube: 637mm (effective)
Bottom bracket drop: 65mm
Bottom bracket height: 310mm
Fork offset: 50mm
Standover height: 768mm
Frame: Reynolds 520 butted chromoly, three bottle mounts, rack and fender mounts, sliding dropouts
Fork: Kona Plus fork, triple mounts, rack and fender mounts
Handlebar: Kona XC/BC riser 780mm, alloy
Stem: Kona XC/BC
Rear derailer: Shimano Deore, 12spd
Shifter: Shimano Deore
Brakes: Shimano Deore MT410, hydraulic disc
Rotors: Shimano Center Lock, 180/160mm, resin pads only
Bottom bracket: Shimano Deore, threaded
Crankset: Shimano Deore, 175mm, 32T
Cassette: Shimano Deore, 10–51T, 12spd
Headset: loose ball
Seatpost: Kona Thumb, 31.6mm
Saddle: WTB Volt
Hubs: Shimano, 148 x 12mm rear, 110 x 15mm front, thru-axles
Rims: WTB ST i30 2.0 TCS, 32h, tubeless ready
Tires: WTB Ranger Light/Fast 29 x 2.6in., tubeless ready
Chain: Shimano Deore
Grips: Kona Key Grip
Contact: Kona Bikes, 2455 Salashan, Ferndale, WA, 98248, email@example.com, konaworld.com