In their own words,
|Over the intervening 31 years, the Stumpjumper has held its place in the Specialized lineup, but their desire to innovate has never stopped and the culmination of those 31 years of development is the Stumpjumper FSR 29 S-Works.|
the Stumpjumper was the bike Specialized built when they "wanted to go farther and push the limits of what was possible on dirt." Launched in 1981, it was the first bike you could buy in your local shop, the first mass-produced mountain bike. Over the intervening 31 years, the Stumpjumper has held its place in the Specialized lineup, but their desire to innovate has never stopped and the culmination of those 31 years of development is the Stumpjumper FSR 29 S-Works. Today, the Stumpjumper sits in the middle of the range - the bridge point between the genre-specific cross-country and gravity bikes, with enough suspension to get a bit rowdy, and performance that is quick and light enough to cover serious distance on - fast. To fit into the commonly tossed around categories, we would pin it in the trail/all-mountain category, a niche we'd be inclined to refer to as "mountain bikes."
The Autosag valve sits to the side of the shock body. Pump it up to about 200psi,
sit on the bike and releasing the air valve auto-corrects for 25-percent sag.
Nestling behind the chain stay is the heart of the Brain system - the inertia valve.
The dramatically oversized BB30 bottom bracket system means there is a huge
mass of carbon at the heart of the frame, which helps keep it stiff.
• Purpose: Trail/All-mountain
• Specialized's FACT 11 carbon construction
• 130mm rear travel with a FOX/Specialized remote Brain with Autosag
• 130mm front travel with a FOX 32 RLC Factory 29
• 69-degree head angle, 450mm chainstays
• Sizes: Small, medium (tested), large, XL
• Frame weight: 6.4lbs (with shock)
• Weight: 23.8lbs (without pedals)
• MSRP: $9,500
While we don't use the word, 'superbike' lightly, the Stumpjumper FSR 29 S-Works fits the bill on every front. Specialized offer a complete range of Stumpjumper bikes, from the base-level Comp 29 at $3000, right up to this S-Works version sitting proudly at the top of the range. From the full-carbon construction, carbon components and SRAM XX groupset, down to the wallet-shaking $9,500 price tag - it's not done by halves. The main frame is made from Specialized's Functional Advanced Composite Technology (FACT) 11 carbon fibre. FACT means that the frame is made from a number of different types of fiber and lay-up techniques, each part being tailored to its specific need for strength, stiffness or flexibility. Paired with the sophisticated carbon structure are a number of features to stiffen the frame, like the giant PF30 bottom bracket at the heart of the frame, the 142 x 12mm rear axle out back and the extra wide bearings that keep the rear suspension moving.
Controlling the 130mm of movement at the rear end is one of the more sophisticated shock systems you'll find on any bike. The Fox Float shock has Specialized's proprietary autosag feature, to help you get you air pressures dialled in with the minimum of fuss. Rather than the usual low-speed compression feature, the Stumpjumper S-Works ensures firm pedalling with another piece of proprietary technology - the Brain. Using an inertia valve mounted on the seat stay, the system can tell the difference between rider forces and trail forces and adapt the shock performance accordingly. The easiest way to think of it is that rider forces come down into the bike and the trail forces come up from the ground. When there is a downwards force it adds on a big chunk of compression damping, like a pro-pedal, and with an upwards force it opens the shock to give you maximum damping performance. All this is done instantly and automatically as you ride, the idea being that you never need to think about your shock being in the right mode, you just ride. Contrastingly, the front is handled by a wonderfully-simple 130mm Fox Float 32 fork with an RLC (rebound, lockout and compression) cartridge - in the more recent version of the bike than the one we tested, this is updated to a CTD damping cartridge.
Throughout the bike the kit is top drawer. While SRAM's XX group has maybe been a little over-shadowed by XX1 recently, it is still light, precise and sexy. The only part of the group-set that isn't from XX are the cranks, which are Specialized's own S-Works, full-carbon arms, mated to a custom SRAM spider and protected by a bash ring. Sitting just behind it is a chain guide mounted on the seatstay, an updated take on the idea used by DCD
back in the 1990s and a simple, but effective way of keeping your chain in order. A pair of Roval carbon wheels get the bike rolling, with a DT Swiss-made rear hub and the spokes at the front are laid out in radial lacing on one side and three-cross on the disc-brake side. A beefy Specialized Purgatory tire is mounted at the front and a fast-rolling Ground Control at the rear - on the test bike, both came mounted tubeless, which is a welcome touch. Their Command Post Blacklight dropper seatpost holds the Body Geometry saddle in place and at the front it is all finished off with a Syntace stem and 720mm carbon handlebar (we swapped this out for with a bar and stem setup we are familiar with).
| (Clockwise) Braking was precise, courtesy of Avid XX discs with 180mm rotors. The Dangler guide hangs from the chainstay. The plastic mech does a good job of keeping the chain in order. At the back end of the drivetrain is a SRAM XX derailleur, mated to a wide-range 11-36t cassette.|
Out on the Trail
Climbing: The Stumpjumper FSR 29 S-Works eats climbs. Weight plays a big factor in this, especially with the big, light wheels and tires, it's simply less to cart up the hill with you. On longer stints, the roomy top tube puts you in a comfortable position to sit there and grind away at the distance. There is a real immediacy in the power transfer to the rear wheel, giving you a sense that virtually none of your energy is being wasted. If you need to get somewhere fast, just stamp on the pedal and the bike shoots forwards like it's alive. When the going got steeper and more technical we were impressed with how well it held traction once you were out of the saddle. There is a compromise at the front, to set the cockpit for descending does raise the bars a touch too high for climbing, so we did have to work to keep the nose down. A travel-adjust system would have solved this, but we prefer the bike without one, we'd rather work a bit harder at the climbs and be ready for every descent.
| The Stumpjumper S-Works 29er climbs easily, even with our DH-height and width handlebars. The Brain shock makes every pedal stroke count.|
Descending: Going downhill, the Stumpjumper's natural home was fast, flowing trails. Carrying speed is the thing it does incredibly well, helped buy the big wheels. You don't need a huge amount of gradient for it to come alive. Once you got moving it was surprisingly playful too, give it nicely-spaced features and you could ride them like a pump track, manualling between hits or popping off them. It does take some work to really wring it out to the limits though. We found ourselves hanging off the side of it like a speeder bike from Star Wars, exaggerating our body posture and moving around the bike, which was an immense amount of fun, but it did take some strength and commitment. It isn't a bike to be forced, on the early rides we were trying to make it jump at every opportunity, but found that it carried better speed when you relaxed and let it take more natural lines, often keeping the wheels on the ground. Yet when the trail encouraged you to jump, it constantly surprised us at how much pop we could get from it with relatively light input.
When the trails got tighter and twistier, the 1147mm wheelbase on the medium we tested meant we could catch the bike out, it was too much to ask to thread it through really sharp corners at speed. The 69 degree head angle also means it's not in its element on steep terrain. On the XC loop, where we put in most of our test mileage, there are a three or four open, rocky sections that you need to attack head-on to take fast. Here we started to find the edges of the Stumpjumper. When we were brave and let the bike go, it battered through with a lot of speed, but it never quite felt comfortable. Whether it was the bike’s light weight, its XC-rated, 32mm-stanchion fork, or its light wheels - or just us being scared of using a $9,500 bike as a plough, it's hard to say. What we are sure of is that when it came time to ride the tougher trails around us, it was the 160mm Enduro we reached for.
We found ourselves looking at burlier forks like the Fox 34 or the Rockshox Pike, thicker tires and the Evo linkage kit (Specialized offer an Evo version of the Stumpjumper FSR 29 which is a bit more gravity-focused). However, we never got further than looking. While it would be interesting to see how far you could push the frame in that direction, inevitably it all adds weight and we felt it would take away from what made this bike so great: the light weight and the speed that comes with that. Those reservations aside, after three months and several hundred kilometers of us hitting everything on our local loops as hard as we could, it was all in one piece and the wheels were still true, so maybe we just need to get used to a bike this light.Component ReportAvid XX brakes:
Good - We were very impressed with the positive lever feel on these, even with the relatively small discs, on the kind of riding this bike excels at, we never felt we wanted anything more. Bad - They did squeal a lot at first, but this quieted down as the pads bedded in.Bashguard and chain tensioner:
Good - It is nice to see attention to chain retention on a bike this light, we didn't have a single problem with the chain in the entire time with the bike and it's something we'd like to see on more bikes. There are also ISCG-05 tabs, giving you the option to mount a chainguide if you want.Command Post Blacklight:
Good - We like the integrated grip clamp/lever. Bad - It did take more attention to keep the post running smoothly than some of its competitors, it worked best if you cleaned the seals and sprayed on some Teflon spray before each ride. In really miserable, gritty UK conditions it did leave us stuck at full extension mid-ride a couple of times.Pinkbike's take:
|There's no escaping the Stumpjumper FSR 29 S-Works’ price tag when summing this bike up. It's the top end of their range and simply out of the reach of most people. Yet, if history tells us anything, it's that before too long, this level of performance will trickle down to the more affordable bikes and that is an exciting prospect for all of us. If this is the future of trail bikes, then the future is quick. It's well-mannered and easy to live with for less-experienced riders and mind-bendingly fast if you want to push it. While the bike does have limits, it's not a big mountain smash bike by any means, but on most trails it's a rocket ship everyone could enjoy, both up and down the hills. - Matt Wragg|
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