One bike for all trails? For the 2025 season, Specialized introduce an overhauled version of the Stumpjumper – one of the oldest models in mountain biking, and a stalwart of the trail bike segment. The latest iteration of the Stumpjumper rolls into the new season with countless clever gadgets and a unique shock concept, and promises to deliver tons of fun on a huge variety of trails. How does Specialized’s evergreen fare on the trail?
1981 was a year of flashy clothes, flammable hairstyles and big pop hits. 1981 was also the year in which Specialized launched the very first Stumpjumper. Since then, a lot has changed in the World, and the Californian manufacturer is now introducing the 15th iteration of the trail evergreen. The Stumpy has always been the “do it all bike” in Specialized’s portfolio, and is known for its excellent all-round characteristics, serving as a template for bikes like the Levo SL. The new Specialized Stumpjumper 15 follows in the footsteps of its predecessors, retailing between € 4,500 (frame kit) and € 13,000 (S-Works). In line with the “One bike to rule all trails” motto, it replaces both the current Stumpjumper and Stumpjumper EVO models, aiming to combine their features and character in just one bike. To achieve this, the new Stumpy relies on a full carbon frame and 29″ wheels, generating 150/145 mm of travel front and rear. The Californians also completely re-designed the suspension, developing a proprietary shock in close collaboration with FOX – but more on that later! How does the new 2025 Specialized Stumpjumper fare on the trail, and can it live up to the legacy of its predecessors? To find out, we travelled to Canada to test the € 9,000 Stumpjumper Pro.
The new 2025 Specialized Stumpjumper in detail
The new Specialized Stumpjumper 15 might not have a wild haircut, but it still comes in a brand-new look which is reminiscent of its electrified sibling, the Turbo Levo SL. The old Stumpy’s distinctive asymmetrical brace is history, and the new frame shape is rounded off by an elegant green paint finish.
For the brake hoses, Specialized still rely on a conventional routing system with cable ports on the head tube. As you’d expect from the Californian brand, the routing system is top notch, preventing annoying rattling on the trail. It’s also interesting to note that the new Stumpjumper forgoes any type of cable routing for a shift cable, meaning that it’s only compatible with electronic drivetrains. Will we see more of this in the future?
Alongside the conventional cable routing concept, Specialized retained and improved many practical features of the Stumpy. Amongst them is the storage compartment in the down tube (aka SWAT Box 4.0) which has been redesigned to allow easy one-handed opening using the long locking lever. Specialized also smooth the edges of the storage compartment to prevent you from ruining your rain jacket when you pull it out from the opening in the frame. Moreover, the new Stumpy features Specialized’s proprietary bottle cage with multitool, which includes all the essential tools for basic trailside repairs – cool!
A rubber cover between the frame and swingarm keeps small rocks from getting stuck in the gap, while a generously sized chainstay protector prevents paint chips and chain slap. A TPU plate on the down tube shields the frame against stray rocks, while a shuttle guard prevents chafing when you throw the bike on the back of a pickup truck.
The new FOX Genie air shock of the 2025 Specialized Stumpjumper in detail.
Specialized’s engineers not only changed the look of the bike, but also went to town with the rear suspension, developing a whole new shock. The result is the new Float GENIE air shock, which was developed in close collaboration with suspension giant FOX. Proprietary suspension is nothing new for Specialized, or for the Stumpy – for much of the 2010s the bike used their “Brain” system, which relies on an inertia valve to open and close the compression damping circuits in the rear shock, locking out the suspension on smooth terrain, but opening it up as soon as the wheel hits an obstacle. Specialized’s latest proprietary suspension system was the Rear Future Shock damper of the Diverge STR gravel bike, which integrated the shock into the top tube, and used the seat tube as a giant spring. As you can see, Specialized are certainly not afraid to try something new – perhaps something to do with their old motto “innovate or die”.
While at first glance, the FOX Float GENIE looks like any other air shock, it hides some special technology on the inside. It has a positive and a negative chamber but forgoes an external reservoir. The special feature of the GENIE is that the positive chamber is divided into an inner and outer air chamber. The inner chamber acts as the main spring, while the outer chamber closes off for the last 30% of the stroke, reducing air volume to increase progression. The chambers are connected by special valves.
The GENIE damper uses the entire volume of the inner and outer air chamber in the first 70% of the travel, which results in a more linear response behaviour, ensuring maximum traction and top sensitivity. When the shock reaches the last 30% of its travel, the piston rod shuts off the valves between the two chambers. This separates the outer air chamber from the inner main chamber, reducing the air volume and making the shock more progressive in the last part of the stroke. This is meant to provide more resistance and prevent harsh bottom-outs.
The new RockShox VIVID air spring damper with hydraulic bottom-out achieves more or less the same result, although using its oil volume rather than the air.
Despite the unusual design, you can still fine-tune the shock’s response behaviour by using special volume spacers, just like with any conventional air shock. The Stumpjumper comes standard with one spacer in the shock. With this set-up, the shock offers a linear response behaviour and releases its travel rather generously. If you add more volume spacers to the chamber, the shock becomes more progressive, which makes it more suitable for flowing trails. Adding the spacers is pretty easy and only requires a little practice: let all the air out, unscrew the air can and clip the two-part spacers onto the shaft – and you don’t even need tools. And no matter which setting you choose, the character of the Stumpjumper remains the same.
Except for the Öhlins spec variant, all Stumpjumper models come standard with the FOX Float GENIE shock, although you can fit pretty much any standard shock with the correct length and stroke.
The spec of the new 2025 Specialized Stumpjumper 15
We tested the new 2025 Specialized Stumpjumper Pro spec variant. Our test bike in size S3 tips the scales at just 13.9 kg. It comes equipped with FOX Factory suspension consisting of a 36 fork with new GRIP X2 damper and FOX Float GENIE air shock, both of which offer countless adjustment options and deliver a tremendous performance on the trail.
Shifting is taken care of by an electronic SRAM X0 Eagle Transmission drivetrain, which relies on a robust direct-mount rear derailleur. SRAM also supply the new MAVEN Silver four-piston brakes, which, in combination with 200 mm rotors front and rear, ensure reliable and powerful deceleration, even on long, steep descents. The Bike Yoke Revive dropper post offers 185 mm of travel in size S3 and can be inserted all the way into the frame, ensuring plenty of freedom of movement on the bike.
For the cockpit, Specialized combine an Industry 9 stem and their in-house, 800 mm Roval Traverse SL carbon handlebars. Roval also supply the new carbon wheelset, which should be slightly more robust than its predecessor. Specialized also rely on their in-house tires, combining a chunky Butcher tire in the soft, grippy T9 rubber compound at the front, and slightly thinner Eliminator in the harder T7 compound at the rear. Both tires rely on the GRID Trail carcass, which is comparable to MAXXIS’ EXO+. However, if you spend lots of time on technical trails, we would recommend upgrading to the more robust GRID Gravity casing.
All spec variants of the new 2025 Specialized Stumpjumper
Alongside the Pro model we tested, there are 3 more Stumpjumper spec variants: Comp, Expert and S-Works. In addition to the conventional spec variants, Specialized also released a special model equipped with Öhlins suspension and TRP DH-R Evo brakes – you can find out more about these in our brake comparison test.
The entry-level Stumpjumper Comp comes equipped with a FOX 36 Rhythm fork and Float GENIE Performance shock, neither of which can keep up with their top-tier counterparts when it comes to adjustability or trail performance. Shifting is taken care of by a new electronic SRAM S1000 Transmission drivetrain. This is based on the GX Eagle Transmission drivetrain, but is only available as OE for bike brands. The S1000 drivetrain will be launched at the same time as the new Specialized Stumpjumper.
The Expert variant sits just below the Pro model we tested and features FOX Performance Elite suspension. The fork relies on the same top-tier GRIP X2 damper as the Factory model and, together with the FOX Float GENIE air shock, delivers the same excellent performance on the trail. Overall, the Stumpjumper Expert has a very sensible spec, which includes a SRAM GX Eagle Transmission drivetrain. Retailing at € 7,500, the Expert might have a little less bling than the higher-end Pro model and top-tier S-Works variant, but it still delivers a tremendous performance on the trail.
For the elegant look and prestigious components of the top-tier S-Works model, you’ll have to fork out a whopping € 13,000. Like the Pro model, it relies on a FOX 36 Grip X2 fork and FOX Float Genie Factory shock. SRAM supply both the electronic XX Eagle Transmission drivetrain and wireless RockShox Reverb AXS dropper post, although the latter offers far less travel than most modern cable-operated posts.
If you want to build your own bike, the new Stumpjumper S-Works is also available as a frameset, which includes a FOX Float GENIE Factory shock, and costs € 4,500
The geometry of the new 2025 Specialized Stumpjumper
Specialized have been using their own S-sizing system for a few years now. This includes a total of 6 sizes, S1 to S6, and allows you to choose the frame size based on your desired reach. Size down for a lively character or size up for more composure. The concept only works because Specialized rely on a short seat tube across the board. Our test bike in size S3 has a short 405 mm seat tube, which still allows you to insert the dropper all the way into the frame – awesome!
The new Stumpjumper has very similar geometry to the current Stumpjumper EVO, and also relies on the same 64.5° head angle. However, this can be adjusted between 63 and 65.5° using the asymmetrical headset cups, which come standard with the bike. There’s also a flip chip in the chainstays, which lets you alter both the chainstay length and bottom bracket height. You can also get an optional shock yoke, which allows you to convert the Stumpjumper from a full 29er to a mullet bike. Sizes S1 and S2 only roll on a mullet set-up.
| Size | S1 | S2 | S3 | S4 | S5 | S6 |
|---|---|---|---|---|---|---|
| Top tube | 541 mm | 573 mm | 595 mm | 624 mm | 647 mm | 597 mm |
| Seat tube | 385 mm | 385 mm | 405 mm | 425 mm | 445 mm | 465 mm |
| Head tube | 95 mm | 100 mm | 110 mm | 125 mm | 140 mm | 155 mm |
| Head angle | 64.5° | 64.5° | 64.5° | 64.5° | 64.5° | 64.5° |
| Seat angle | 77° | 76.5° | 77° | 76.5° | 77.3° | 77.6° |
| Chainstay | 430 mm | 432 mm | 435 mm | 435 mm | 445 mm | 445 mm |
| BB Drop | 41 mm | 38 mm | 38 mm | 38 mm | 38 mm | 38 mm |
| Wheelbase | 1,149 mm | 1,181 mm | 1,213 mm | 1,244 mm | 1,285 mm | 1,322 mm |
| Reach | 400 mm | 425 mm | 450mm | 475 mm | 500 mm | 530 mm |
| Stack | 608 mm | 618 mm | 627 mm | 640 mm | 654 mm | 667 mm |
The new 2025 Specialized Stumpjumper on the trail
On level ground, the Stumpjumper places you in an upright, comfortable pedalling position. When the gradient increases, the front wheel remains planted on the ground, even on steeper climbs. If you turn into a technical climb, the rear suspension generates good traction on loose forest soil, with minimal pedal bob. This makes the Specialized Stumpjumper a very efficient climber, even without the climb switch, meaning that you’ll have plenty of energy for epic descents even after a long day in the saddle.
When gravity takes over, the Stumpjumper integrates you deeply into the frame, and the weight is evenly distributed between the front and rear. As a result, the Specialized makes you feel at ease from the get go, and encourages you to open the taps, regardless of your riding skills. Especially on flowing trails, the Stumpjumper invites you to play with the terrain, making it easy to flick the bike from one side of the trail to the other, and to pop off ledges. At the same time, it implements steering input quickly and predictably, while slapping a massive grin on your face in the process.
The capable suspension has a major effect on the bike’s character. Setting up the shock with lots of volume spacers produces a progressive response best suited to flowing trails. This allows you to generate tons of speed by pumping through rollers and berms. When riding on rougher trails, we recommend the standard setting with one volume spacer. This allows the shock to release a generous amount of travel and makes you feel as if you were riding a more capable bike. At the same time, the suspension doesn’t blow through its travel too abruptly, offering enough reserves when you botch a landing or ride through a root carpet – your ankles will thank you!
Even on tough enduro trails, the Stumpy has your back, making it easy to plough through nasty rock gardens. The integrated riding position and intuitive handling inspire great amounts of confidence, allowing you to negotiate even steep rock slabs without going into panic mode, while the powerful SRAM MAVEN brakes allow you to control the bike when you get to the bottom of the chute. Whether you’re riding fast flow trails or technical singletrack, the Specialized Stumpjumper delivers a high fun factor on a huge variety of trails.
Who should take a closer look at the new 2025 Specialized Stumpjumper?
The 2025 Specialized Stumpjumper is a great option if you’re looking for a trail bike for all sorts of riding scenarios, whether it’s a leisurely post-work cruise on your home trails or an epic weekend expedition on technical singletracks, regardless of whether you’re a beginner or an advanced rider. If you want a bike with countless clever details and a well thought-out overall concept, you should take a closer look at the new Stumpjumper.
Our conclusions about the 2025 Specialized Stumpjumper
The new Specialized Stumpjumper 2025 sets a new trend with its proprietary shock and exclusive electronic shifting, combining this with a fresh look and Specialized’s sophisticated detail solutions. Moreover, it combines the features of its two predecessors into one bike, which makes it a loyal companion for a huge variety of riding scenarios, whether it’s fast-paced flow trails or technical singletrack. The Stumpjumper doesn’t want to be pigeonholed, appealing to both beginners and advanced riders with its intuitive handling and huge feel-good factor.
Tops
- Intuitive handling suitable for both beginners and advanced riders
- Sensitive rear suspension
- Clever detail solutions
- Huge fun factor on a variety of trails
Flops
- Pricey
For more info, visit specialized.com
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Words: Mike Hunger Photos: Rodrigo Vicente, Specialized
