Many (Dirty) Hands, One (Awesome) Bike

Over 50 R&D teammates, each and every one a trail rider, worked for more than three years to develop the Stumpjumper 15.

Thank God Some Kids Stayed in Science Club

Evidence-Based Performance for Riders

The Specialized Science Club creates our full-suspension bikes by developing the chassis, geometry, kinematics, and suspension components as an integrated whole, delivering unmatched performance to riders. While they touched every aspect of the Stumpjumper 15, their crown jewel is GENIE—a best-of-both-worlds suspension tech marvel that'll have you floating over trails like a magic carpet ride.

Thank God, indeed.

Crush Like a Big Bike, Jib Like a Jumper

GENIE Devours Bumps and Provides a Playful Platform

GENIE provides a platform you can trust in the turns or when pumping the backside. The second-stage rising rate makes for a fun, playful bike that can still plow like a bike with much more travel. Truly “best of both worlds” rideability.

With both air chambers open, GENIE air volume is massive, resulting in a much flatter spring curve for the first 70% of the shock’s stroke.

With 30% stroke remaining, an internal band closes the ports to the secondary air chamber, reducing the overall volume and increasing the spring rate.

The last 30% of stroke has a significantly more progressive spring rate, preventing bottom-outs and providing a platform for stability and a poppy feel.

Grade On a Curve, GENIE Gets an “A”

Spring Curve Detail

The graph illustrates the relationship between bump force and wheel travel of Stumpjumper 15 and Stumpjumper EVO. Note that 1,080 Newton impact force results in 101 MM of travel on the Stumpjumper 15 and Enduro, whereas the Stumpjumper EVO only uses 87 MM of travel to absorb the same force.

First Graph Title Wheel Force to Travel Comparison

Compared to other air shocks on the market, GENIE allows for a lower spring rate earlier in the stroke, with a higher ramp later in the ending stroke (see graph). This means that with GENIE's “softer spring,” we will use more travel to absorb the same amount of energy, resulting in superior

Frame of Reference

Form Follows Fun

We engineered the FACT 11M carbon and M5 Alloy chassis – front end, rear end, and the link between them – as a single unit that hits the stiffness target we established for trail riding.

Anti Squat

The Ride Dynamics team establishes optimal anti-squat targets for each riding experience. As the quintessential trail bike, Stumpjumper 15 balances efficiency and optimal bump force management. We found the sweet spot after analyzing extensive quantitative data and qualitative feedback.

Capability and Control by the Numbers

Geometry Honed to Rule All Trails

The Stumpjumper 15 geometry delivers big bike capability when you need it, a nimble feel in tight sections, and lively, efficient climbing manners. The generous cockpit centers you on the bike, optimizing traction and corner control. The low bottom bracket, slack head tube angle, and optimized fork offset keep things stable in the rough. Three rear-center dimensions across the size range optimize handling for riders of different sizes.

Have it Your Way

Benchmark Geo Adjustability

Seamlessly integrated adjustability makes Stumpjumper 15 the most personalizable trail bike ever. Six distinct geometry settings allow you to hone its performance for any style, any terrain. The head angle is adjustable to three settings between 63 and 65.5 degrees via a unique eccentric upper headset cup. Fine-tune the bottom bracket height up or down by 7mm by swapping the Horst link chips. Drop it down for a more stable ride, or set it high for clearance.

S-Sizing

Select the Size that Suits Your Style (Not Your Inseam)

S-Sizing is based on what matters: rider style, not inseam. Six sizes, all with similar head tube lengths and standover, allow you to choose the size that best suits how you ride. Smaller S-Size numbers will be more nimble, thanks to their shorter reach and front-center measurement, while bigger S-Sizes deliver more stability and a roomier ride.

Stumpjumper 15 roll on Traverse SL II Wheels

Carefully Engineered to be Ridden Recklessly

Smoother is Faster

The Traverse SL II delivers terrain-hugging and bump-force absorbing control through its 21% greater vertical compliance, made possible by the shallow and wide rim shape and front/rear specific layup. The new rim also boasts a 15% increase in front wheel strength and 25% rear wheel strength compared to its predecessor. Additionally, the rim shape is engineered to “ankle,” providing adaptive rotation for improved traction and control.

Flats Be Gone

Spend your time on the trail instead of next to it. The patent-pending, optimized "Flat Top" bead profile of Traverse wheels significantly reduces pinch flats by requiring an impressive 85% more force compared to a standard round bead.

Air Time

Thank our genius engineer Chuck Teixeira for inventing the “Roval ThreadBed Valve,” a valve that threads directly into the rim, eliminating compression nuts and air loss from rim flex, making tire set-up easier, and reducing sealant clogs.