Review: The Specialized Stumpjumper ST Comp Carbon 29 may be shorter on travel, but it ain’t short on fun

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Earlier this year Wil had the pleasure of heading out to Spain for the launch of the new Specialized Stumpjumpers. We’ve now had the Stumpjumper ST Comp Carbon 29 (130/120mm) and Stumpjumper Expert Carbon 29 (150/140mm) back on test to see how they perform on more familiar trails. Here we have Rachel reviewing the shorter travel Stumpjumper ST. Over to Rachel!


The headline news from Specialized is that for 2019 there are three different Stumpjumper platforms in the range:

  • Stumpjumper ST (short travel; 130mm front, 130/120mm rear)
  • Stumpjumper (150mm front, 150/140mm rear)
  • Stumpjumper EVO (150mm front, 130/140mm rear)
specialized stumpjumper st
Specialized has completely revamped its classic Stumpjumper for 2019.

Each platform is available with 29in or 27.5in wheels (the rear travel of each is 10mm less on the 29ers) and in a variety of build options including a women’s specific option (same frame but smaller components, shock tuned for lower weights). To make things a bit easier to keep track of, the women’s specific bikes like the Rhyme and the shorter travel Camber have been subsumed into the Stumpy range.


The shorter travel Stumpjumper ST is a new name in the Stumpy range, coming in to replace the Camber. Like its predecessor it’s designed to be a trail bike but one that’s a bit quicker and more direct when you’re on the pedals. I regularly ride and reach the limits of my XC full-susser on bigger trails so was keen to see how a more trail orientated short-travel 29er would compare.

There are four models in the Stumpjumper ST range, starting off at £1,700 and going up to £8,000 for the carbon S-Works. The Comp Carbon tested here sells for £3,500, and comes in Small through to X-Large frame sizes, with the 27.5in version offering an X-Small size too.

specialized stumpjumper st
The Stumpjumper ST, shown here, replaces the Camber as Specialized’s short travel trail bike.

The Bike

There’s lots of background about the development and attributes of the new Stumpjumper in Wil’s write up of the launch. If you’re a detail person head over there and I’ll try and keep things shorter here.

The ST gets the same new Stumpjumper frame as the longer travel models, but runs a smaller shock and also a shorter 130mm travel fork to give the complete bike a steeper head angle, a lower front end and a lower BB height.

specialized stumpjumper st
The frame is the same as the long travel version, but a shorter stroke shock brings the travel down to 120mm.

In direct comparison with the outgoing Camber, the Stumpy ST is predictably longer, lower and slacker. Reach on the medium is 435mm (an 8mm increase) and the head angle a whole degree slacker at 67.5o. Combined, these changes increase the front centre of the bike and total wheelbase by 26mm to a reasonable 1161mm on the medium.

The rear geometry is more similar to before with a 437mm chainstay length and a tidy 75.1o seat tube angle. There’s a Flip Chip at the lower shock mount, which allows you to change the head angle by 0.5o and alter the BB height by 6mm. The default position and quoted geometry is in the ‘low’ position so swapping over will make things steeper and higher.

One of the most obvious features of the Stumpjumper is its asymmetric sidearm taken from the Demo DH bike that increases the stiffness of the frame and provides a reinforced loading point for the suspension linkage. In photos it looks quite striking but isn’t that noticeable in the flesh particularly on the dark finish of the Comp Carbon.

specialized stumpjumper st
Where’d he go??
specialized stumpjumper st
Oh phew! There he is!

A major development for Specialized was to optimise the bike to perform with the latest metric air shocks to achieve a linear feel of the suspension. Each shock is tuned specifically to each of the Stumpy platforms to achieve this ‘Rx Trail Tune’. The ST Comp Carbon gets a Fox Float DPS rear shock with a Fox Float Rhythm 34 up front.

Just like the £8,000 S-Works model, the ST Comp Carbon uses a FACT 11m carbon fibre frame (previously the lower price-point carbon bikes had an alloy rear end). Other features include a beefed up SWAT compartment with a redesigned door to make more room for your snacks and it easier to get to them.

specialized stumpjumper st swat bottle cage
Snack box and beverage parking.

There are permanent cable guide tubes to make re-routing easier too. Assuming this works, it’s a great feature but as I didn’t change any of the cables whilst I had the bike, it’s not one I’ve tested out. The final frame development is a thick contoured chainstay protector to reduce chain slap noise. A small detail in the grand scheme of things but it seems to work surprisingly well.

The drivetrain on the Comp is a mix of Shimano SLX (shifter and cassette) and XT 11-speed (derailleur) with RaceFace Aeffect cranks and a KMC chain. The cranks are a sensible 170mm length given the hefty 39mm BB drop, and I didn’t experience any pedal strike problems even on some pretty lumpy trails.

specialized stumpjumper st race face aeffect
The Race Face cranks spin through a classic threaded bottom bracket shell.

It’s worth noting that all the 29er Stumpys have a 30t chainring regardless of their travel and whether they run a SRAM cassette with a 50t or a Shimano with a 46t. I found that on less steep and longer rides I’d have preferred a 32t ring as I didn’t need the little gears and spun out a bit at the other end. You may want to change the chainring size to better suit your usual terrain and leg power.

Although the drivetrain mix and Shimano SLX brakes are obviously specced in order for the Comp to meet its price point there was nothing lacking in the performance. In fact, the Shimano SLX brakes were far more reliable than the Guide Rs on the longer-travel Stumpjumper I’ve also been testing.

specialized stumpjumper st shimano slx brake disc rotor
The SLX stoppers are top notch performers. No complaints here.

There’s an X-Fusion Manic dropper post (125mm on Small, 150mm on M-XL sizes), which functioned exactly how a dropper post should function. Bear in mind that if you’re not a fan of the X-Fusion, the bigger 34.9mm seat tube will limit your aftermarket dropper choices unless you use a shim.

The rest of the Comp build is Specialized in-house. There are Roval Traverse Boost wheels with a 29mm inner width alloy rim and Roval branded DT Swiss hubs. The 2.3in Butcher GRID (front) and Purgatory GRID (rear) do look a bit skinny for the job but there’s clearance for up to a 2.8in tyre if you do want something chunkier. Spesh’s 6061 alloy bars are 780mm wide and the Trail stem 45mm on all sizes.

specialized stumpjumper st
For a short travel trail bike, Specialized has kept the stems short (45mm) and the bars wide (780mm).

The Ride


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2019 Specialized Stumpjumper ST Comp Carbon 29

  • Frame // FACT 11m Carbon Fibre, 120mm Travel
  • Fork // Fox Float Rhythm 34, 51mm offset, 130mm travel
  • Shock // Fox Float DPS Performance, Rx Trail Tune
  • Hubs // Specialized sealed cartridge bearings, 110x15mm Front & 148x12mm Rear
  • Rims // Roval Traverse 29, hookless alloy, 29mm inner width, tubeless ready, 28h
  • Tyres // Specialized Butcher GRID 2.3in Front & Purgatory GRID Rear
  • Crankset // RaceFace Aeffect, 170mm Arm Length, 30t Chainring
  • Rear Mech // Shimano XT, GS cage, 11-speed
  • Shifters // Shimano SLX, 11-speed
  • Cassette // Shimano SLX, 11-46t
  • Brakes // Shimano SLX, 200mm Front & 180mm Rear Rotors
  • Stem // Specialized Trail, Forged Alloy, 31.8mm Diameter, 40mm Length
  • Bars // Specialized Trail, 7050 Alloy, 31.8mm Diameter, 27mm Rise, 780mm Wide
  • Grips // Specialized Sip Grip Half-Waffle Lock-On
  • Seatpost // X-Fusion Manic, 150mm
  • Saddle // Specialized Body Geometry Phenom Comp, 143mm Width
  • Size Tested // Medium
  • Sizes Available // Small, Medium, Large, X-Large
  • RRP // £3,500

Review Info

Brand:Specialized
Product:Stumpjumper ST Comp Carbon 29
From:Specialized, specialized.com
Price:£3,500
Tested:by Rachel Sokal for 2 months

Comments (8)

  1. 2.3 on 29mm rims are now narrow?? They seem pretty big on my Solaris Max (same tyres as tested too), even compared to the 2.8 on 40mm rims parked next to them. Not tried 2.6 on either yet, maybe they are the Goldilocks’ tyres 🙂

    Nice looking bike that though.

  2. Waited six months to get a demo on the 29St (was putting money by to pay for it) and finally got hold of one a fortnight ago. Came away underwhelmed if I’m honest, after reading lots of reviews and listening to users was expecting more. Not a bad bike but ended up with a Whyte s-120 instead. Tracked better through the berms and was just more fun. Moto: Always demo before you buy.

  3. @brassnet – it’s weird how times change, I remember thinking how massive a 2.2” tyre was when I first rode one. The Spesh tyres come up a bit narrow compared to others so it might be a matter of trying a different brand rather than a different stated width.

  4. Surely if you wanted to fit a dropper with a narrower diameter you could just buy one of those seat tube reducer shims?

  5. What size was the test bike, and what was the weight please?

  6. Oops. I see the size in the review now. Do you have the weight too?

  7. @jamesfifield – as you’ve seen we tested a medium, it weighed in at 14.5kg on our scales.

    @mcvittees – shimming is an obvious option and I know plenty of people who do it but has its risks. As shims are only 100mm long then you tend to need to over tighten the clamp to get the post to hold. As well as risking the frame it can also compress the dropper internals so it doesn’t work properly (seems unlikely but I know a couple of people who have had this).

    Rachel

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