If you are steadying yourself because you already saw
the $9900 price tag, take a deep breath. Specialized
offers the Stumpjumper FSR 29 and 26-inch-wheeled
versions at various price points. Specialized didn’t build
the S-Works to hit a predetermined budget; instead, they
built this bike to see how far they could push the boundaries of the modern-day trailbike. Friends, we’ll tell you
now, they have pushed the boundaries to a point where
others will have to play catch-up.
WHO IS IT MADE FOR?
The Stumpjumper is for the trail rider who likes to be
challenged by rocky/rooty trails, steep descents and 4-foot
drops and doesn’t want to get left behind on the climbs.
The S-Works Stumpjumper FSR Carbon 29 (we’ll call it
“S-Works” for the rest of the test) does all these things
with one difference—it doesn’t hang in there on the
climbs; it makes the others chase. WHAT IS IT MADE FROM? The frame and stays, are all carbon fiber. The frame
geometry is optimized for 29-inch wheels. The FSR
rear suspension pivots on full-cartridge bearings and is
controlled by the Fox/Specialized Brain shock (more on
that in a minute). The bottom bracket is a PressFit 30,
and the rear-wheel spacing is 142 millimeters.
WHICH COMPONENTS STAND OUT?
The Specialized product managers pulled out all the
stops, gracing the S-Works with Specialized-developed
components like the carbon fiber cranks and rims, Roval hubs, dropper seatpost, carbon fiber bar, tires (mixed and matched to boost performance), grips, and even a chainstay pad. Little touches—like the bumpers on the ends of the crankarms and the adhesive rub guards on their sides—demonstrate that Specialized knows if you are spending this much money for a mountain bike, you want to keep it looking great.
Specialized’s “Brain” shock technology is a
breath of fresh air. The remote compensator
chamber near the rear hub houses an inertia
valve. This inertia valve (a cylindrical brass
weight) senses when the rear wheel is taking
a hit from the trail (as opposed to the rider’s
pedaling) and opens the shock’s damping
circuit. This keeps the suspension
firm for pedaling and supple
for soaking up bumps.
A “Trail Tune”
adjustment (they call
this “Brain Fade”)
allows a rider to
dial in the point
where the shock
active. But wait,
that’s not all.
feature for their shock.
This is the biggest
advancement in rear-
suspension performance since
elastomer bumpers were cast into the dumpster. Don’t
understand rear-suspension sag? You don’t have to with
Autosag. Pump the shock to any ridiculously high psi
setting you want, sit on the bike, push the Autosag valve,
and the rear suspension adjusts to the perfect sag setting
automatically. Don’t like Specialized telling you what that
is? No problem. You can still add or remove air from the
HOW DOES IT PERFORM?
Setup: You got the scoop on the shock. The fork has two travel settings. Begin in the long-travel mode and dial in
about an inch of sag. The fork has Fox’s CTD modes
(Climb, Trail, Descend) with Trail Tune, which allows you
to choose between three firmness options while in the Trail
mode. Since CTD is the polar opposite of the Brain in its
approach to suspension, we recommend you try to mimic
the Brain performance by running the fork in “Trail” mode
using the firmest Trail Tune setting.
Ergonomics: This is a big bike. A few of the wrecking
crew fall into that gray area where a medium or large frame will fit. Not with this bike. The large-size frame is for large riders or riders under 5 foot 11 with Kermit the Frog-length legs. The rider sits inside the bike, but you still sense a slightly rearward weight bias. The riding position is upright and proved more comfortable the longer the ride. The bar is plenty wide, while the saddle is on the racer-firm side of comfort.
Moving out: The S-Works has big wheels, meaty tires
and a 2x10 drivetrain, so you don’t expect explosive
acceleration. Surprise. The S-Works takes every watt of
your power and turns it into forward momentum. The
carbon rims certainly help. And with the laterally rigid
bottom-bracket area and carbon cranks, you can get up to
speed fast with less effort.
Cornering: The S-Works inspires confidence
immediately. The bottom bracket height feels lower than it
measures, and the active suspension works great, allowing
the bike to carve corners even when the terrain is chattery.
The suspension remains active when needed.
The super-light, unsprung weight of the bike helps this and
keeps the bike moving through its travel exactly when it’s
needed. Small-bump compliance was a shocker. Riders who
have not experienced the Brain shock with Trail Tune
don’t believe it can tune out all the chatter, but it does. The
only caveat is that the bike’s long wheelbase makes tight
switchbacks a bit of a balancing act.
In the rough: Our loops are littered with sections that
raise the adrenaline level and cannot always be cleaned
while riding a 26er. Not so on the S-Works. Whereas riders
on smaller-wheeled bikes need to ride aggressively to stay
on top of rocks, roots and ruts, the S-Works rider can remain in a comfort zone and still clear sections going either up or down a trail. We had to get used to using a slightly larger gear than normal, because the S-Works allows you to. We had better success torqueing through sections than spinning through them.
Climbing: Use the same trick as above. Go outside
your comfort zone and push a slightly bigger gear. This
bike will motor. Drop the fork travel? We never did.
Turn the fork to Climb mode? Again, we never did.
Descending: Drop that saddle with a push on the
remote lever and let it rip. We caught ourselves picking
lines like we were riding a 26er, which is the wrong way
to ride this bike. The beauty of these wheels is you can
get very creative with mixing rocks, ruts and obstacles
into your line. No reason to avoid them. That’s a good
thing, because the long wheelbase does not serve well
for quick line changes.
These tires will find their way onto other brands; they
are that good. We intentionally tried crazy off-camber
sections just to see what it would take for the S-Works
Purgatory tire to reach its limit. We seldom could get it
to slip. It was amazing, and that was with tubes.
Tubeless would be even more amazing.
Braking: The Shimano stoppers proved plenty
powerful for these big wheels, but they did get noisy
when hot. The 7-inch rotor in the rear (the front is an
8-incher) proved to be the worst offender.
TRICKS, UPGRADES OR TIPS?
We removed the chainguide and noticed a slight
increase in chain noise on the descents, but not enough
to bug us. Plus, the drivetrain works smoother without
it. If you are an aggressive rider (jumping and banging
down rocks), leaving it on will add some dropped-chain
Do yourself a favor; find your favorite Trail-mode
setting on the fork and forget messing with Climb or
Descend modes. Leave the TALAS (Travel Adjustable
Linear Air Spring) in its full-travel setting. This strategy
will produce the best suspension balance between front
Pull the tubes from the tires and convert to tubeless.
Since our trails are hardpacked most of the year, we’d be
tempted to give up a bit of the bite and durability of the
stock tires in favor of a lighter tire like the Specialized
Renegade or Fast Trak. Talk about blasting off.
The Specialized Command Post Blacklite dropper
seatpost’s remote lever is ergonomically awkward. It
requires a twist of the wrist to get the thumb on top of it
and a lot of effort to activate it. We have been spoiled by
both the KS Lev and RockShox Reverb posts, and if we
could afford a $9900 bike, we’d keep the Blacklite for a
backup and substitute one of the two mentioned above.
This is the best beginner mountain bike we have ever
tested, and we’re not being wise guys. The S-Works
handles scary terrain exceptionally well, even if its pilot
is a bit tentative. It tracks through or floats above loose,
sandy terrain effortlessly. It claws its way through rock gardens like the Mars rover. It hammers along singletrack or rockets up climbs without asking its pilot to make any adjustment to its suspension. In general, it forgives your mistakes. In the hands of an experienced rider, there really is no limit.