Mtb specialized stumpjumper 26. Specialized Stumpjumper EVO 27.5

Scott Genius ST 900 Tuned review

  • Brand: Scott
  • Product: Genius ST 900
  • Price: £10,999
  • From: Scott Sports
  • Review by: Benji for 3 months


  • Good all-rounder geometry
  • Excellent rear suspension
  • Mega stiff (if you like that sort of thing)
  • Restrictive cockpit combo
  • TracLoc is redundant on such a sorted suspension layout
  • Mega stiff (if you don’t like that sort of thing)

The latest Genius is the sixth incarnation and the first revision of the platform for five years. This is the ST version of the Genius. ST stands for Super Trail by the way, not Short Travel (which is sometimes what ST means on other brands’ bikes, nor Single Track).

If it helps you understand this bike, think of the Genius ST as Scott’s version of a Specialized Stumpjumper Evo. That’s a comparison that helped me anyway! The Genius ST is the radder Genius. It comes with adjustable headset cups and everything. The ST ships in the slackest headset cup (and will most likely never be adjusted from that). The build kit of the Genius ST bikes is a bit more gravity-centric too: piggyback shocks, bigger brakes etc.

As regards the whys and wherefores of the ‘900’ and the ‘Tuned’ suffixes; they both essentially mean This Is The Top Carbon Model. And yeah. £10,999. Bananas.

There is an all-alloy Scott Genius ST 920 for £4,999, which I would absolutely bear in mind whilst you read the rest of this review.

The vital stats of the Scott Genius ST are that it’s a 150mm travel 29er with a 160mm fork. The geometry is pretty much as progressive as it gets (details later). And there’s loads of proprietary and/or integrated and/or internal stuff on it.

The thing you can’t see

The most eye-catching internal thing being the rear shock. Scott purchased Bold Cycles a few years ago and have used their hidden-shock layout on various bikes since. Most notably the Spark. And now it’s on the Genius and Genius ST range.

Is there any actual point to having a hidden shock aside from aesthetics? Even if the answer was “no”, I’d not have a problem with it. Aesthetics and uniqueness are nice things in their own right.

As it is I do actually think there are some benefits to containing the rear shock inside the frame. It protects the shock from filth and flying rocks. It makes the bike easier to clean (especially on this wireless AXS drivetrain Genius ST).

And without wishing to spoil the rest of this review, I think the location of the shock/pivots/rockers is key to the great performance of the Genius ST’s rear suspension. Without enveloping the shock inside the seat tube (nad having an interrupted seat tube instead) there would be issues with dropper insertion and generally having the shock right in the filthiest part of the bike. Specialized Enduro anyone?

Hiding the shock does have a couple of drawbacks. Shock overheating and adjustment faff. The first one I personally think is irrelevant (in the UK at least). The extra faff of air pressure adjustment or damping adjustment is a trickier proposition. It totally depends how much of a knob twiddler you are. Sure, it’s faffy when you’re setting up the bike for the first couple of rides but it’s not that bad. The cover is really easy to remove/replace. And once you’ve got the bike set-up, chances are you’ll rarely open the cover much at all during your ownership of the bike.

In terms of setting sag – and keeping an eye of general rear travel usage – the in-built travel-o-meter on the non-driveside main pivot is great. Certainly loads easier than mm tape-measuring O-rings on suspension shafts that don’t have gradients printed on them (ie. anything non-RockShox).

TracLoc and load

As regards the other proprietary/integrated/internal stuff. I’m going to cop out as just say “it is, what it is”. It’s not like any of it is a surprise to anyone who buys this bike. You can see right away all the ‘TracLoc’ control levers on the handlebars. And the routing going through the headset.

For what it’s worth, I surprisingly found myself having not problem at with the multi-lever TracLoc. But I do think that thru-headset cabling is wholly without virtue.

“TracLoc?” you ask. What is TracLoc? It’s the multi-lever thing on the left side of the handlebar that can switch the rear shock between three different settings. It does not do anything to the fork. The three different settings are called Open, Ramp Control and Climb.

The TracLoc control has three levers in total. The bottom one is the dropper post lever. The middle lever pulls the rear shock through the modes (Open Ramp Control Climb). The top lever releases the rear shock through the modes in the opposite order (Climb Ramp Control Open).

Climb closes the compression circuit to a virtual Lockout.

Ramp Control basically closes off a section of the air chamber and thus acts a bit like a volume spacer; ramping up the latter stage of travel use. This intended for dealing with hard landings and other such Big Events.

Open is, er. open. It is worth pointing out that there is still Low Speed Compression (LSC) adjustment available on the rear shock. The compression damping isn’t just limited to the three TracLoc modes. So, Open more accurately puts the shock into whatever LSC setting you’ve dialled into it. Which could be loads of LSC.

Despite all the armchair teeth-suckers, I can say that somewhat surprisingly, I never once operated the dropper post lever instead of the TracLoc levers (or vice versa) by accident. It’s a very well designed control in my opinion. So there. I will say that when releasing the TracLoc into the next setting the released lever can give you a surprisingly firm rap on the index finger if you’re not careful. You do quickly adapt however and learn not to leave your finger in the firing line.

Now then. Perhaps the principal reason I didn’t have much of an issue with the whole TracLoc thang was that I didn’t find myself having much of a need to use it. I’ll come out and say that the Genius ST has the best 4-bar suspension performance I’ve ever experienced in terms of a trail bike. It is impressively stable under pedalling (even with minimal LSC) and has bags of mid-stroke support.

I dabbled a bit with the Ramp Control setting but whether it’s because I weigh 73kg and/or don’t really do much in the way of hucking, I didn’t really feel Open setting was overly linear. Your (air) mileage may vary. At least it is there if do find yourself flying through the travel too readily.

Ultimately, I rode in Open setting almost all the time (apart from engaging Climb setting in a placebo-stylee when bonking on tarmac or being late for the school run etc!)

specialized, stumpjumper

Despite Scott no doubt wanting the TracLoc to be a vital USP of the Genius ST, if I owned a Genius ST I’d probably remove it and get a simple dropper lever to go in its place.

Stash stuff

The history of the Specialized Stumpjumper

Specialized introduced the Stumpjumper in 1981, the first mass-production mountain bike. In the early days of the sport, riders had to choose between cruisers modified for off-road use (often known as “klunkers”) or expensive custom bikes made by a few small builders.This 2007 Stumpjumper Classic is a reproduction of the original Stumpjumper, made to celebrate its 25th anniversary.

The Stumpjumper was an affordable alternative that matched the geometry and performance of custom, purpose-built mountain bikes. The original Stumpjumper produced in Japan was based on a custom Lighthouse Cycles Chaparral mountain bike designed by Tim Neenan. The Stumpjumper is considered historically significant enough to be on display in the Smithsonian.

Ned Overend’s race-winning 1992 Stumpjumper M2.

As mountain biking evolved, so did the Stumpjumper. The original was a fully-rigid, steel-framed XC bike. In 1991, Specialized introduced the first Stumpjumper M2 which used a lightweight aluminum frame. Former world Champion and legendary XC racer Ned Overend rode the Stumpjumper M2 hardtail to win the NORBA national championships in 1991 and 1992, along with two World Cup victories.

A 2016 Stumpjumper Pro 29 HT, the final year of the Stumpjumper hardtail.

The hardtail version of the Stumpjumper (sometimes named “Stumpjumper HT”) was the flagship XC hardtail in Specialized’s line-up until 2017 when it was replaced with the Epic Hardtail. The Stumpjumper HT has since been discontinued, and for the purpose of simplicity, this guide will only FOCUS on full-suspension models.

The Stumpujumper’s famous FSR suspension is easy to identify thanks to the pivot just in front of the rear axle.

In 1993, Specialized introduced the first full-suspension Stumpjumper, the Stumpjumper FSR. It used Specialized’s FSR suspension system, which stands for “Future Shock Rear,” a four-bar suspension or Horst-link design. This design has been used on all full-suspension Stumpjumpers with the exception of the new 2021 carbon Stumpjumper.

Former downhill world Champion Miranda Miller descending hard on a 2019 S-Works Stumpjumper. Photo courtesy of Specialized Bicycles.

Over time, the full-suspension Stumpjumper evolved from an XC bike into a mid-travel trail bike. It now caters to riders who want a capable all-rounder for both climbing and descending. Proving its modern descending prowess, former world Champion Jared Graves raced the Stumpjumper in the Enduro World Series from 2016-2019 and won the Aspen/Snowmass round in 2017. For the majority of trail riders, the Stumpjumper is the perfect do-it-all bike.

Specialized Stumpjumper build levels explained

S-Works Stumpjumpers are easy to identify thanks to the S-Works banding.

Specialized offers the Stumpjumper in different component trims, which are indicated by the model name. The Stumpjumper hierarchy ranked from lowest to highest is:

These builds vary in the component spec level.

For 2019 models, Specialized also offers a base-level Stumpjumper below Comp, with an aluminum frame and basic components.

Stumpjumper Comp

As an entry-level build, a Stumpjumper Comp will use less expensive, entry-level components (cockpit, suspension, drivetrain, wheels).

specialized, stumpjumper

Stumpjumper Comp models are also available with either carbon or aluminum frames. This is often designated in the model name (e.g. Stumpjumper Comp Alloy vs. Stumpjumper Comp Carbon).

S-Works Stumpjumper

The premium offering, an S-Works Stumpjumper, will use top-of-the-line components and the highest grade carbon fiber in the frame.

In general, as builds get higher-end they will be have better drivetrains, better suspension, lighter, more feature packed components, and have better resale value.

Some special-edition models like the Stumpjumper Coil and Stumpjumper Pemberton LTD Edition fall outside the normal hierarchy but are generally around the Pro or S-Works level.

16-2018 Specialized Stumpjumper models

This generation of Stumpjumper came in three versions based on wheel size:


  • This is the first Stumpjumper generation with Boost hub spacing — a 12x148mm rear axle and 15x110mm fork.
  • All models use proprietary rear shocks with “Autosag,” which helps riders easily dial-in suspension sag. To set-up, over-inflate the air chamber so the bike is totally extended, sit on the bike with the shock fully open, then press the Autosag button to bleed out the excess air. It automatically sets the Stumpjumper to around 25% sag.
  • Because of the proprietary shock mount, this generation Stumpjumper is not compatible with aftermarket shocks. However, custom aftermarket suspension yokes are available if riders wish to swap the Specialized specific shock for an aftermarket shock.
  • This is the first generation to use the Specialized SWAT door, a storage system built into the downtube for carrying spare tubes, tools, food, or other small items. The SWAT door is only available on carbon models.
  • The Stumpjumper Comp Carbon and Expert frames are built with a FACT 9m carbon front triangle and the M5 aluminum rear triangle.
  • Stumpjumper Pro and S-Works frames are full carbon, with a FACT 11m carbon front and rear triangle.

Specialized Stumpjumper 29

2018 Specialized Stumpjumper Comp Carbon 29 sold at The Pro’s Closet

Wheel size: 29”Suspension travel: 150mm front / 135mm rearHead tube angle: 67°Seat tube angle: 74°Reach: 413mm (M) / 431mm (L)

Specialized Stumpjumper 650b

2018 Specialized Stumpjumper Comp Carbon 650b sold at The Pro’s Closet

Wheel size: 27.5”Suspension travel: 150mm front / 150mm rearHead tube angle: 67°Seat tube angle: 74°Reach: 413mm (M) / 431mm (L)

Specialized Stumpjumper 6Fattie

This is the only Stumpjumper generation to offer the 6Fattie version, which uses 2.8-3.0” wide 27.5-plus tires for more comfort and traction.

2018 Specialized S-Works Stumpjumper 6Fattie sold at The Pro’s Closet

Wheel size: 27.5” PlusSuspension travel: 150mm front / 135mm rearHead tube angle: 67°Seat tube angle: 74°Reach: 413mm (M) / 431mm (L)

19-2020 Specialized Stumpjumper models

This generation of Stumpjumper came in six versions offering different options for suspension travel, geometry, and wheel size:


specialized, stumpjumper
  • Redesigned from the ground up with an asymmetric carbon frame based on the previous generation’s Specialized Demo downhill bike. A carbon arm extends around the right side of the rear shock adding support and lateral stiffness for better tracking through rough terrain.
  • Geometry was tweaked to be slightly longer and slacker than the previous generation.
  • The suspension kinematics were made more progressive to reduce bottom-out during big hits.
  • The proprietary shock mount and Autosag were eliminated, so this generation Stumpjumper is compatible with most aftermarket shocks.
  • A flip chip was added to the rear shock yoke to adjust between high and low geometry positions. Bikes come from the factory in the low position. Flipping to the high position steepens the head angle 0.5° and raises the bottom bracket 6mm for more agility.
  • All carbon frames from Comp to S-Works use a full carbon FACT 11m front and rear triangle.
  • SWAT door on carbon models.
  • Specialized also introduced the Stumpjumper ST or “short travel” variant and reintroduced the downhill-focused Stumpjumper EVO variant.
  • The Stumpjumper 6Fattie was discontinued for the 2019 model year, but Stumpjumper 27.5 models have enough clearance to fit up to 27.5 x 3.0 plus tires.

Specialized Stumpjumper 29

2019 Specialized S-works Stumpjumper 29 sold at The Pro’s Closet.

Wheel size: 29”Suspension travel: 150mm front / 140mm rearHead tube angle: 66.5°Seat tube angle: 74.8°Reach: 425mm (M) / 445mm (L)

Specialized Stumpjumper 27.5

2019 Specialized S-works Stumpjumper 27.5 sold at The Pro’s Closet

Wheel size: 27.5” Suspension travel: 150mm front / 150mm rearHead tube angle: 65.5°Seat tube angle: 75°Reach: 435mm (M) / 455mm (L)

Specialized Stumpjumper ST

The Stumpjumper ST takes the standard Stumpjumper platform and reduces the travel by 20mm. The reduced travel combined with slightly steeper geometry means the bike will feel more agile and efficient than the standard Stumpjumper, ideal for people who ride mellower trails. The Stumpjumper ST replaced the Camber in Specialized’s line-up.

Specialized Stumpjumper ST 29

2019 Specialized Stumpjumper ST Comp Carbon 29 Womens sold at The Pro’s Closet

Wheel size: 29”Suspension travel: 130mm front / 120mm rearHead tube angle: 67.5°Seat tube angle: 75.5°Reach: 435mm (M) / 455mm (L)

Specialized Stumpjumper ST 27.5

2019 Specialzied S-Works Stumpjumper ST 27.5 sold at The Pro’s Closet

Wheel size: 27.5” Suspension travel: 130mm front / 130mm rearHead tube angle: 66.5°Seat tube angle: 76°Reach: 444mm (M) / 465mm (L)

Specialized Stumpjumper EVO

To increase downhill performance, Specialized experimented with the Stumpjumper’s geometry. The Stumpjumper EVO had a longer reach and an impressively slack 63.5-degree head tube, making it the most progressive bike in Specialized’s line-up at the time. It was also the first Stumpjumper to come equipped with a reduced offset fork.

The 2019 Stumpjumper Evo also was the first to use Specialized’s S-sizing system. This does away with traditional small, medium, and large sizes, and focuses on reach and wheelbase. Standover clearance and stack height remain relatively low across sizes, so riders can choose their size based on their desired length.

This generation Stumpjumper EVO only came in two sizes, S2 and S3, which roughly equate to medium and large.

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