Review – Specialized S-Works Stumpjumper 29

The ever-evolving trail bike


The Stumpjumper is one of the most iconic bikes on the trail with a history that goes back to the start of mountain biking. While the “Big S” has released several versions of the Stumpy, Specialized is confident this is the best one yet. From 26-inch to 29-inch, steel to carbon, the Stumpjumper has seen every iteration of modern technology you can imagine. And for 2018, the Stumpy has a new frame concept and suspension tune.


The Stumpjumper was designed for everything from lightweight trail riding to steeper, more technical terrain. Our test bike comes with 29-inch wheels and 140mm of rear travel with 2.6-inch-wide tires. This combination puts the bike in a more aggressive trail category for more technical riding. Specialized offers the aluminum version of the Stumpjumper starting as low as $1,850. The S-Works build is Specialized’s highest-end bike in this category, with a price tag that will probably only appeal to a committed rider at $9,500.


There are a lot of new features built into this generation of the Stumpy and some proven technologies that have been carried over. For 2018, Specialized kept the FSR suspension but went with a new shock sizing and tune. Specialized scrapped its proprietary shock size to allow riders the opportunity to swap shocks aftermarket. The stock shocks use Specialized’s RX tune that was designed to work specifically with the company’s suspension design.

Aside from the revamped FSR suspension, Specialized went with a completely new sidearm frame design that exposes the shock on the one side, similar to the Orbea Rallon. Specialized claims this design allowed them to shave weight while stiffening up the frame for more predictable handling. Along with the new frame design is Specialized’s Swat Box built into the downtube that allows for enough storage to fit a spare tube and other small items. The Swat Box can be easily accessed under the bottle cage.

Riders should rejoice, as threaded bottom brackets are making a comeback on mountain bikes. The new Stumpy ditched the previous PF30 design for the more reliable threaded version. Adding to the user friendliness of the Stumpy is internal cable routing with tubes built into the frame. This essentially allows a rider to push the cables through the frame without any headaches.

There are several versions of the Stumpjumper available, ranging in travel and wheel size. Our test bike is the highest-end S-Works version that uses Specialized’s Fact 11 carbon, which is the lightest layup Specialized offers. The Stumpy has a full carbon fiber frame and rear triangle with a new chainstay protector. There are plenty of modern bits wrapping up the frame design, such as Boost rear spacing and a flip chip to allow riders to adjust the geometry. Specialized made the geometry on this version is slightly more progressive than before, but not overly so.


With a price tag of $9500, you can imagine that our Stumpjumper had just about every bell and whistle available. The Fox Factory suspension offered plenty of adjustment for our test riders, while the SRAM XX1 Eagle drivetrain was as consistent as we expected. Specialized spec’d its Phenom Expert saddle, which worked well for all of our test riders. Saddle fit is very subjective, but we were impressed with the comfort level.


Suspension setup: New for this year, Specialized offers a complete tuning guide for all of its mountain bikes. We followed the recommendations, putting 20-percent sag in the fork and set- ting up the rebound for our local trails. The shock was a bit more complex than we expected. We started at 26-percent sag and the recommended rebound setting, with the open-mode adjust six clicks in. We tried this setup for a couple of rides, but opted for only two clicks on the open-mode adjust for a little smoother ride on minor trail chatter.

Moving out: Our test bike came stock with 2.6 tires in the front and rear on 29-inch hoops. Specialized recommended running the pressures around 17–20 psi, which worked well for our local trails. The stock 780mm bars felt comfortable in conjunction with the 50mm stem.

Cornering: This Stumpy is a bike that feels comfortable in corners, especially at high speeds. The beefy Butcher front tire with Gripton compound has plenty of support and traction to allow riders to lean the bike over confidently. Even on loose-over-hard terrain, the front tire seemed to have endless grip. At high speeds, the extra traction from the tire provided a very stable feel. On tighter corners at lower speeds, the Stumpy was easy to control and didn’t wander.

Climbing: Hitting the climbs, the Stumpjumper wasn’t the liveliest bike we’ve ridden. The geometry was comfortable, and the pedaling platform was efficient with the shock in the middle setting. The rear Purgatory tire hooked up well on steep terrain, but the overall tire spec wasn’t the fastest-rolling we have ridden in recent memory. With the shock in the middle setting, we did notice just how stiff the frame was, especially when pedaling hard out of the saddle. The Stumpjumper isn’t out to set PRs on the climbs, but it will get you to the top of the mountain comfortably.

Descending: Opening up the suspension and pointing the Stumpy downhill, it lived up to the hype of being fast and planted. The Stumpjumper isn’t a bike to take things slowly. It feels best running wide open, easily rolling over anything in its path. With the rear shock open, the suspension was active and tracked well. The larger 2.6 tires don’t make for very playful handling, but instead respond with a predictable ride that feels secure. The stock 160mm dropper post gave us all the clearance we needed to lean back over the rear wheel when descending steep pitches of trail and technical terrain.

Braking: Our test bike came with SRAM Guide RSC, which provided consistent performance, even on some warmer days. The Purgatory rear tire added to the confident braking with plenty of traction, even on looser sections of trail.


The stock dropper post worked consistently during our testing, but was loud when moving up and down. If you’re picky about noise coming from your bike, you may want to look into a different dropper. While the stock 2.6 tires had plenty of grip, we experimented with a narrower set of 2.4 and 2.5 tires that gave the Stumpy a little extra speed without compromising traction. After a couple months of transportation to and from the trails, the paint on the frame began to fade quite a bit. We would recommend sticking with one of the builds that has a less extreme color.


The new Stumpjumper is a modern iteration of a legacy bike that has progressively evolved in the decades since it first appeared. Still, while some companies are pushing the boundaries with geometry and suspension design, Specialized has instead found its niche with a comfortable, but slower paced balance of technical innovation. The top end S-Works carries a steep price tag that for us, exceeds the boundaries of a plausible cost/benefit analysis. For our money we wouldn’t recommend this model, but the lower-priced versions are a much better buy.


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