THE GEOMETRY OF CONTROL

The generous cockpit centers you on the bike, improving traction and corner control. The low bottom bracket, slack headtube angle and reduced fork offset keep things stable in the rough. A steep seat tube optimizes power output and climbing balance. Short chainstays keep things nimble.

*Weight of a painted production S-4 Stumpjumper frame including paint, shock, assembly hardware, link, carbon extension, molded downtube and chainstay protectors, axle, seat clamp.

HEY LAZY CARBON, BEAT IT!

The shape of a composite frame determines the vast majority of that frame’s weight, stiffness and durability. After crunching countless Finite Element Analysis calculations, we optimized the shape of each of the Stumpy’s frame tubes and their intersections, eliminating “lazy” material that would otherwise hide in unoptimized corners. This ensures that every fiber is delivering the most strength and stiffness it can, resulting in maximum performance and minimal weight.

THE CAVIAR OF CARBON FIBER

To achieve breakthrough weight and stiffness goals, the Stumpjumper employs the strongest, most expensive carbon we have ever used in a mountain bike frame.  The result? Climbing speed and flickable handling of a light weight, along with stiffness that delivers wicked pedaling efficiency and telepathic handling.  You really can have it all.

RIDER FIRST

Our Rider-First Engineered™ process delivers the optimal balance of tuned stiffness, weight and ride quality from all six sizes, ensuring every rider experiences the same ultimate trail ride characteristics.

SIZE MATTERS

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

ONE-PIECE REAR TRIANGLE

Stumpjumper’s one-piece rear triangle improves torsional and lateral stiffness, which in turn enhances responsiveness and pedaling efficiency. These lateral and torsional stiffness gains are achieved by eliminating the flex intrinsic in mechanical pivots.

FlexStay

Through precise shaping of the seatstays and chainstays, along with utilization of appropriate composites, we created a flex zone along the seatstay, above the brake mount, that flexes to allow suspension travel without any rear end pivot hardware.

THE MISSING LINK

All in all, the FlexStay allows us to ditch 55-grams of hardware, enhance lateral chassis stiffness, reduce maintenance, and precisely match suspension kinematics and chassis stiffness. The result? The most efficient, nimble, trail bike we’ve ever made.

SHRED IN SILENCE

You won’t realize how much chain-slap was bumming your ride until it’s gone. Our chainstay protector makes the drivetrain virtually silent by disrupting the sine-wave of an unchecked chain clattering away in the rough. The result is the transcendent silence of one hand clapping.

STUMPJUMPER CREATORS

Being tasked with creating the rippingest trail bike we’ve ever made is no small feat. Steve Saletnik, Peter Denk, Matthias Segerer, Chance Ferro, Kayla Clarot, Luke Beemer, Fred Chiu, Tero Jakku, and more than a dozen others dug into every aspect of engineering, suspension dynamics, design, and R&D to do exactly that.