Reportage

Shredding With the Stone Eaters: Knolly Tyaughton Steel 29er Hardtail Review

On a recent Radavist Retreat, John and Hailey left their wintery homes to ride the various trails and gravelly terrain down in Phoenix with Josh. While there, John rode the Knolly Tyaughton Steel he’d procured from the brand earlier this winter and spent time riding amongst the Stone Eaters of South Mountain Park. Find out what he thought about this wild hardtail 29er with an even wilder price point ($2,449 complete) below!

Stone Eaters

Xeric plants, or plants that have adapted to extremely dry and arid climates, don’t live in detritus-filled soil. Cacti don’t crave compost. Excessively moist soil will kill them by rotting their roots. No, these hardened plants have evolved to live amongst rocky outcroppings, in sandy arroyos, between boulders, on cliff faces, and within igneous lava fields to be close to their favorite food: stone.

Cacti are Stone Eaters, and no cactus is more iconic than the almighty saguaro, Carnegiea gigantea. These indicator species of the Sonoran Desert are part of a monotypic genus, meaning there is but one species within that genus. A healthy saguaro, allowed to live out its life with the right conditions, can grow to heights over 12 meters tall. Fittingly, the saguaro blossom is the state wildflower of Arizona.

The saguaro, like other cacti found throughout the Sonoran desert—ocotillo, cholla, opuntia, hedgehog, and barrel—all grow in this area due to the incredibly arid environment. A true desert receives less than 10″ of precipitation a year, and while you will find cacti throughout less arid regions, they thrive in soil that drains.

Cacti break down rocks into minerals, and over time, their seeds will be eaten by birds and mammals and pooped out on rock escarpments, where the cycle then continues. When you ride in places like South Mountain in Phoenix, you are in the Stone Eaters’ domain, as they have literally shaped the landscape.

I rode the size XL with a Deore kit and a Marzocchi 150 mm fork, it weighed 33.4 lb.

Enter the Tyaughton

Knolly Bikes is a small company based in the southwest of British Columbia. The brand’s genesis dates back to late 2003 when the founder, Noel Buckley, designed a run of prototype V-tach frames that were delivered to paying customers later in 2004. For the next two years, Noel worked on his modus operandi before solidifying Knolly in 2006 and launching their first three bike models in 2007.

While the brand primarily focuses on full-suspension bikes for its rowdy free-riding locale, the Tyaughton Steel is its second-ever hardtail model. It’s available in both a steel chassis, as shown here, and a titanium chassis.

Although the Tyaughton was designed for the southwest of BC, I felt like the southwestern US might offer up some unexpected similarities in terrain. While these two ecoregions sit in contrast when it comes to annual precipitation, rocks, green flora, steep, punchy climbs, and tech descents all fall into the overlap of their Venn Diagram.

The Tyaughton is slack, it’s steep, it’s long; reminiscent of 2023’s Chromag Darco review we documented in this exact terra, yet it’s a hardtail. So how did it stack up? We’ll get into that shortly!

Quick Hits

  • Four sizes: Small, Medium, Large, XL
  • Tig-welded Chromoly Frame, made in Taiwan
  • Specced with a 150 mm fork but can be over-forked to 160 mm
  • Complete as reviewed weight: 33.4 lb
  • 157Trail rear end, 157 mm wide, allowing for a healthy chain line and max chainring of 36t
  • Consistent head tube 64.5º and seat tube angles of 75º across all four sizes
  • Driveside chainstay yoke
  • 427 mm chainstay length
  • Shorter seat tubes with long insertion depths to run longer dropper posts
  • External cable routing, except for the dropper post
  • ISCG 5 bash guard tab
  • Price as reviewed: $2,449 Deore Kit
  • Highest price point: $3,009 with XT Kit
  • Frame $699

 

 

Knolly utilizes “Human Centric Sizing” to determine these reach and stack numbers, allowing a broad(er) range of human bodies to fit across just four sizes. 

Run the Numbers

With a 64.5º head angle, a 75º seat angle, a bottom bracket height of 323 mm (or about 12.7″), and a setup with 29 x 2.3″/2.5″ tires, it’s easy to see that the Tyaughton is a true-to-form long and slack hardtail. The XL sports a whopping 522 mm of reach, meaning from the tip of the saddle to the handlebar center at the stem clamp is around 24″, what I like to call “extension” as a bike fit metric.

That’s the longest XL hardtail I’ve reviewed to date! And that’s a good thing. XL bikes are usually not long enough. I’m only 6’2″, so imagine what a 6’5″ and up rider feels! Knolly’s properly sized bikes have attracted taller riders to the brand over the years for this very reason.

What I love about the Tyaughton’s geo is the properly tall stack height of 652 mm. Combined with a 150 mm travel fork and a long reach, the bike felt like a truly aggressive hardtail under me. Or rather, I felt like I was riding in the bike, not on the bike.

Frame Detailing

Every bike has a standout detail, or at least it should. While the Tyaughton’s tig-welded Chromoly chassis feels appropriately standard, this beautiful chainstay yoke is my favorite part of the bike. Designed to fit a 36t chainring—thanks to the Super Boost spacing of the rear, 157 mm—the yoke nests well within that clearance triangle equation: chainring, tire, and chainstay. This results in a 54 – 57 mm chainline, with a spread of  55 – 56.5 mm being optimal for drivetrain health. The Tyaughton pedals quietly, even in the biggest cog on the Deore cassette, thanks to this optimized chainline.

Many wheel builders and bike designers, like Charlie Cunningham, argued a wider-spaced rear hub (as long as the hub flanges are also wider) makes for a stronger wheel overall.

The Tyaughton was specced with a 2.3″ Maxxis DHR2 tire in the rear and a 2.5″ DHF in the front, but I opted for some extra cushion found with the 2.6″ Teravail Kessel tires for the rocky terrain (thank you, Stone Eaters!) out in Phoenix. The frame also accommodates a 27.5 x 2.8″ or 3″ tire. The Deore crankset comes with a 32t chainring, but if it were my build, I’d run a 28t.

Other details found on this biologic-looking frame profile are the IS44 upper and IS56 lower head tube diameters, external cable guides—tucked away under the top tube and perfectly positioned to keep from scraping your inner thighs—and an elegant droop in the top tube, which provides plenty of room for body language in the air or in the steeps.

The branding is tasteful, with a tan logo on the downtube, one on the top tube, a nice-n-shiny head tube badge, and a reminder that Knolly has been around since 2003. There’s even a ISCG-05 tab that’s removable if you should want to run a chainring bash guard.

While the frame is nice and long, it’s a shame Knolly didn’t put more bosses on the bike for extra water bottles, tool rolls, or the like. Two measly bosses are better than none, I suppose? Look how dwarfed our large 32 oz Expedition bottle is by that frame triangle space! Yikes…

Parts Spec: Lower Tier with None of the Fear

Shimano’s Deore drivetrain should not be conflated with its previous attachment to the Deore XT catalog. However, modern Deore is still worthy of flying that flag. First introduced in 1983, Deore, or “Deer Head,” as it was previously called, changed the evolution of the mountain bike forever. With one fell swoop, Shimano established itself as a brand with a vested interest in the sport.

I revisited Deore during a hardtail review in 2020, and my opinion remains mostly the same. Throughout the Tyaughton test period, I found that the only required maintenance was a few turns of the barrel adjuster. It shifted great under load, as an MTB kit should. And aside from a less-than-sexy audible “KLUNK” when ratcheting down the cassette on a pedal-y descent, it provided a relatively quiet ride.

To shave some dollars off the spec, Knolly inserted an SLX crank and opted for Shimano Deore 4 Piston M6120 brakes. Again, they are not the best feeling brakes out there, especially when compared to the higher spec XT 4 Piston M8120, but they get’er done.

What was a pleasant surprise in the lower-tier Deore build kit was the SDG Tellis dropper specced with 200 mm of travel (on my review bike). Knolly typically sells the complete with a 170 mm travel Tellis, which maxed right out on the seat post collar at my 81 cm saddle height. The Tellis is a great dropper post and one that is worthy of its own review at a later date.

The Tyaughton comes with a 150 mm travel fork and can be over-forked to 160 mm. I didn’t feel like it needed any additional travel, though!

Rounding out the build spec are the lower-tier DT Swiss M1900 wheels. While they stayed true and continued to spin straight, even without tire inserts, the bummer for me was the 370 hubs, which only have 18 points of engagement and three pawls. This leaves you with a dead space of engagement that is only noticeable when you are ratcheting your pedals for better foot position.

Unfortunately, in rocky terrain on a hardtail, where you already have less traction on the rear wheel due to the lack of suspension and, thus, have to rely heavily on foot and wheel placement, it can take some getting used to. I wouldn’t call this hub spec a deal breaker, but remember, this is 157 mm Super Boost rear wheel, so unless you have a 157 rear wheel already, you might want to upgrade the freehub body in the 370 rear hub to the newer DT 370 Ratchet LN one, which costs around $150.

I’m 6′ 2″ with long legs, long arms, and weigh 190 lb. I fit perfectly on the size XL.

On the front, providing a plush yet stiff and predictable steering track is the 44 mm offset Marzocchi Z1 29” fork with 150 mm of travel. Marzocchi, since being acquired by Fox, has stepped up its game, and the Z1 is on spec with the lower-tier Fox forks (i.e. non-Factory Performance spec.) I moved between three and five clicks of rebound from closed and my appropriate air for my 190 lb self.

What was great about riding the Tyaughton is it was good to go for riding in chunky and loose Phoenix trails. All it took were a few pumps of the shock pump and some new rubber. The bike is extremely capable out of the box and if you wanted to build one up with your own parts, $699 for a frame is a deal!

Chutes and Radders: Riding the Tyaughton on South Mountain

Last year, we shot the Chromag Darco, another BC brand, in this terrain, so I felt it was appropriate to try out a hardtail with a similar geometry in the same trail network. I loved the Darco, and felt like it was a crowning achievement for Chromag, so much so that we even awarded it “MTB of the Year” last year. Even though other media poo poo-ed it, I felt like its Horst link rear travel made for seemingly limitless support in this terrain.

A lot of people made claims that the Darco was “like a hardtail.” My friends, it is nothing like a hardtail, especially in this terrain. It has a rear shock! This landscape is rough, filled with brake-bumped corners where there is “dirt”–South Mountain is primarily decomposed granite–metamorphic gneiss, chunky rocky escarpments with wheel-sized holes, blind drops, and lots of abrupt, steep, and punchy climbs. Riding a hardtail is much rowdier than a bike with rear suspension, regardless of travel length! Riding a hardtail on South Mountain is even rowdier.

While this terrain is often better suited for a more “well-rounded” geometry (think slacker seat angle, slightly shorter reach, and a tad steeper head angle), bikes like the Tyaughton proclaim prowess when the trail opens up and steepens. Even those long, flat rock gardens were a breeze—as long as you had speed—and the bike’s high-ish bottom bracket, compared to other similar bikes, made for very few pedal strikes.

One place the bike did get hung up on was in steep and undulating rocky climbs, but I’d attribute that more to the lower engagement of the rear hub than the bike’s geometry.

Where I absolutely loved the Tyaughton was on the slabs. The longer reach allowed for lots of fore/aft movement, the higher stack (yay!) and 150 mm of travel kept me from feeling front-heavy. Overall, the bike came alive in super steep, butt-puckering terrain, especially if you can really turn up the intensity and go just a little bit faster down it.

Yet, while this long and slack bike existed symbiotically on rocky outcroppings with the Stone Eaters, the geometry made it feel more planted and hesitant to pop off jibs and booters. Riding back to the Pima trailhead, it still enjoyed being jibbed along the trail-side hits.

Popping up to a tire tap felt natural and flowy, while gapping a step-like boulder on a particularly rocky descent took a lot of lifting, as illustrated in the two photos above.

Still, a bike like a hardtail is all about compromises. By definition, it has no rear travel. But the frame itself, when paired with a fat tire, is plenty flexy and didn’t leave me feeling beaten up by the end of the descent. Its stability in the steeps and at high speed was appreciated, and thanks to the tukt rear end, it made for easy maneuvering on tight and off-camber switchbacks.

For being a long bike, at 1281 mm or 50.4″, the Tyaughton was able to find the path of least resistance with surprising ease. Its anthropomorphism would be akin to a Western yellow-bellied racer snake, Coluber constrictor mormon: Fast, agile, and long!

Take Away and the TL;DR

It’d be easy for a brand like Knolly to ignore the humble hardtail in its lineup. Yet, nestled right in amongst the heroic full-suspension models is a rad little bike that still holds true to the brand’s southwestern BC roots. While we ain’t got no loam, ladder runs, or a lot of moisture, the Tyaughton felt right at home in the desert southwest of the United States. It’s incredibly sure-footed at high speeds, loves steep terrain, and while its wheelbase in size XL can feel cumbersome in tight rocky areas, just add some extra pepper to your pedal, and you’ll be amazed at how well it navigates those moments at speed.

While I wouldn’t call this a beginner’s hardtail, I’d argue it’s for a rider who is adept at riding a full suspension, looking for something a little more challenging to make their backyard trails more engaging and—yeah—fun! It was right at home amongst the Stone Eaters, and I enjoyed getting it covered in the remnants of erosion in the Sonoran Desert.

Many thanks to Knolly for sending me a Tyaughton to review. We might not be their core media audience, but the Tyaughton is a core hardtail. … and its price point of $2,449 is very tempting!

Pros

  • INSANE pricing! $2,499 for this complete and/or $699 for a frame!
  • Progressive geometry: slack/steep/long
  • Higher than normal bottom bracket for a bike of this phenotype
  • Bomber build kit
  • Exceptionally adapted to steep terrain
  • Handles speed like a cracked-out javelina!
  • Super Boost rear makes for a strong wheel and healthy chainline

 

Cons

  • One bottle. :-(
  • Bike might be too progressive for new or beginner riders
  • Rear hub engagement is low, but the freehub is upgradable to the newer Ratchet LN body
  • Super Boost rear means you can’t swap your Boost wheels over

 

See more at Knolly.

Thanks to Josh for nailing the riding shots!