The Ultimate Review of 2025 Specialized Stumpjumper 15 | The Best All-In-One Mountain Bike?

The “big S”, Specialized, the “red S”, “Sweetest bicycle koolaid manufacturer”…. whatever you may refer to the brand of Specialized as, it’s undoubtable that if you’re a mountain biker know about Specialized’s presence in the mountain bike world. Back in 1981 Specialized was the first to bring a production mountain bike to the world. Today, 43 years later marks the launch of the 15th iteration of that bike, the Stumpjumper.

Spending the last three years in development, we see many changes to the Stumpjumper platform which is pitched as the ‘one trail bike to rule them all’ with the single biggest innovation on the new model being GENIE. GENIE is a game-changing air spring technology, that grants every trail rider’s three wishes: suppler feel and control of a coil spring, better bottom-out prevention than a standard air spring, and a tuneable “platform” for a playful feel.

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The benefits of a big travel bike and a short travel bike all in one. Specialized is onto something here, bikes intended purpose is becoming so niche, the Stumpjumper 15 broadens substantially despite the sensible 150mm/145mm suspension platform. The ability to eat bumps larger than larger travel bikes and absorb them like nothing Specialized claims GENIE’s magic carpet boasts 57% less traction loss time and 39% fewer severe bottom out events.

We will see a full six frame sizes with varying front AND rear centre figures with reach ranging from 400mm to a whopping 530mm. On top of that, riders get all the usual things we love about Stumpjumper, adjustable head angle, adjustable BB height, SWAT downtube storage, great spec across models, an Ohlins Coil Edition, SRAM Maven brakes and wireless ONLY shifting, yes you heard us correctly!

Carbon models start at $8900 equipped with what looks to be a OEM unreleased SRAM S1000 Transmission wireless rear derailleur and Maven Brakes right through to the S-Works model for $19500 and a S-Works frameset at $6800.

We have been putting the Stumpjumper 15 Expert through its paces down in Canberra and will have more on it, GENIE and how it performs on the trails very
soon.

MORE ON THE MODELS

Stumpjumper Comp 

• Lightweight FACT 11m carbon chassis and rear-end
• Robust Specialized alloy wheels with sealed cartridge bearings
• Ride Dynamics tuned FOX FLOAT Performance with Specialized GENIE air spring technology provides maximum grip and traction found in a linear coil spring, bottom-out prevention found in a progressive air spring, and the ability to tune mid-stroke and end stroke support independently. 2-position open and firm damper adjustments.
• Eat up the chunkiest trails with the FOX FLOAT 36 Rhythm fork with GRIP damper
• Smooth and precise shifting from SRAM Eagle T-Type AXS drivetrain
• Big braking power from SRAM Maven Bronze 4-piston brakes
• Trustworthy time and time again X-Fusion Manic dropper position

Stumpjumper 15 Öhlins Coil

• Lightweight FACT 11m carbon chassis and rear-end
• Incredibly tough Roval Traverse wheels with DT Swiss 370 hub
• Premium suspension support from an Öhlins TTX 22 M Coil, Ride Dynamics tuned
• Plow through anything with a 160mm Öhlins RXF38 M.2 29 fork
• Reliable and smooth shifting from SRAM GX Eagle AXS T-Type drivetrain
• Powerful brakes with great hand feel thanks to TRP DH-R EVO 4-piston brakes
• Adjustable travel PNW LOAM dropper post
• Lifetime replacement of suspension pivot bearings to the original owner

Stumpjumper Expert 

• Lightweight FACT 11m carbon chassis and rear-end
• Ride Dynamics tuned FOX FLOAT Performance Elite with Specialized GENIE air spring technology provides maximum grip and traction found in a linear coil spring, bottom-out prevention found in a progressive air spring, and the ability to tune mid-stroke and end-stroke support independently. Highly adjustable2-position open and firm mode with the 3-
  position open mode compression adjuster.
• Supportive and tuneable FOX FLOAT 36 Performance Elite fork with GRIP X2damper
• Strong and trusted Roval Traverse wheels, DT Swiss 370 hub
• Smooth and precise SRAM GX Eagle T-Type AXS
  drivetrain
• Powerful and reliable SRAM Maven Bronze 4-piston brakes
• Adjustable travel with PNW LOAM dropper post
• Lifetime replacement of suspension pivot bearings to the original owner

Stumpjumper 15 Pro

• Lightweight FACT 11m carbon chassis and rear-end
• Super-light and durable Roval Traverse SL wheels, Industry Nine 1/1 hub
• Ride Dynamics tuned FOX FLOAT Factory with Specialized GENIE air spring technology provides maximum grip and traction found in a linear coil spring, bottom-out prevention found in a progressive air spring, and the ability to tunemid-stroke and end-stroke support independently. Highly adjustable 2-position open and firm mode with the 3-position open mode compression adjuster.
• Supportive and tuneable FOX FLOAT 36 Factory fork with GRIP X2 damper
• Smooth and precise SRAM XO Eagle T-Type AXS drivetrain
• Big stopping power from SRAM Maven Silver, 4-piston brakes
• Slam your saddle with Bike Yoke Revive Max’s ultra-low stack dropper post

Stumpjumper S Works

• Lightweight FACT 11m carbon chassis, rear-end, and link
• The lightest high-performance Roval Traverse SL wheels, DT Swiss 240 hub
• Ride Dynamics tuned FOX FLOAT Factory with Specialized GENIE patent-pending air spring technology provides maximum grip and traction found in a linear coil spring, bottom-out prevention found in a progressive air spring, and the ability to tune mid-stroke and end-stroke support independently. Highly adjustable 2-position open and firm mode with 3-position open mode compression adjuster.
• Supportive and tuneable FOX FLOAT 36 Factory fork with GRIP X2 damper
• Strong and precise SRAM XX Eagle T-Type AXS drivetrain
• Super-powered braking from SRAM Maven Ultimate 4-piston brakes
• Smooth and reliable RockShox Reverb AXS dropper post

INITIAL IMPRESSIONS

Its not often we get sent a unreleased model, let alone one that has been built and setup up for us out of the box, nothing left to chance by the team at Specialized. We of course can never help ourselves and we pull apart, prod and poke the bike and its apparent that Specialized has stepped it up yet again, refined, clean lines, unobtrusive hardware that won’t snag on clothing or retain debris and moisture it’s the real deal.

The Stumpjumper 15 Expert model we have on review is an S4 with a 475mm reach, selected for us based on my preferred range of 460mm to 485mm range at 178cm tall. The S4 is one of six sizes across the range but with such generous stand over many riders could ride one of two frames size based on ride style or preference.

The Expert model has the pick of the line-up in terms of value for money. Equipped with all the latest and durable fruit, the stuff riders mechanics alike wish companies would just install from the get go. The Expert model we have on review Has a Grip X2 damped Fox Performance Elite 36 fork upfront with 150mm of travel and a Performance Elite GENIE rear shock out back with 145mm of rear travel. Stopping is taken care of by the most powerful brake I’ve ever used on a
bike; the all new SRAM Maven Bronze (ironically Grey in colour to match the GX Transmission Group-set). Fitting such a powerful brake to a trail bike is a bold statement or testament to Specialized’s intended use of the Stumpjumper 15.

Back to that mention of SRAM’s GX Transmission group-set, and we don’t see any cable ports for them’ pesky cable things. There is a fully sleeved port for the rear brake line, an internally sleeved port on the other side of the headtube for an internally routed Dropper cable and that’s it, no exit ports out of the mainframe and certainly no ports into the UDH ready swing arms. So unless Shimano is about to drop a wireless Di2 with self powered rear derailleur it looks like the big S has destined the Stumpjumper 15 for the fully wireless digital age!

As our bike was built by the team at Specialized AU it was dialled out of the box, the carpark test got us thinking the shock was on the soft side…like way too soft despite the team setting it up for us and GENIE giving us 30% sag. We felt like we were falling through the travel to bottom out, in our carpark Birkenstocks ride, so we upped the pressure from 170psi to 240psi and still thought we could bottom it out. After a few back and forward emails and call found we could tune the outer can with bands provided and were offered a polite “well you should just ride it first before you fiddle chat” and we hit the trail to find out.

Unexpectedly, it turns out that the huge air can is so supple and “coil like” that at the correct sag of 30% the bike is incredibly linear like a coil just hugging the ground as it goes along. However, as the large outer chamber closes the air is crammed into the GENIE’s bottle and ramps up something savage. I don’t think we ever felt the bottom.

For more info on the Specialized Stumpjumper 15 head to specialized.com