All of you die-hard alloy fans can rejoice. Yes, the new Stumpjumper ST comes in an alloy version, and it may be the most radically designed alloy bike ever made. And with new tube shapes and an asymmetrical design, the Stumpjumper ST Alloy 29 is sure to exceed your expectations of how a trail bike should ride.
Our design goal for the new Stumpjumper was simple—build the ultimate trail bike, one that feels telepathic. And it turns out that this feeling all comes down to stiffness. Think of it this way: when the frame's telling your hands one thing and your feet another, your brain gets confused with the imbalance and the bike feels unstable. In order to fix this, we had to get to work on dialing-in the materials and shapes.
We continued down the suspension path with a custom Rx Trail Tune on both the fork and rear shock. Suspension performance is highly dependent on frame, wheel, and rider size, so we use our Rx Tune to get each bike to land in the middle of the adjustment spectrum, and this gives you the biggest possible range to fine-tune your ride. Another focal point of the tune was matching the suspension characteristics between wheel sizes—we developed a specific Rx Tune for each platform. So, no matter what wheel size you prefer, you'll get perfectly linear suspension.
Steps were also taken to make this bike easy to live with. Threaded bottom brackets make a triumphant return, and we made room for up to a 3.0" tire. You're also free to run whatever aftermarket rear shock you want, since we're using standard metric shocks. And customization is furthered with a Flip Chip that lets you to dial-in your Stumpy to your riding style. Switch it from High to Low and it drops your bottom bracket 6mm and slackens the head tube by half-a-degree. Little details also jump out to surprise you, like a newly designed ribbed chainstay protector that makes chain slap a thing of the past and nearly silences the drivetrain.
The build here is no-nonsense with a focus on dependable, high-performing parts, like Shimano SLX front and rear derailleurs, Tektro Gemini disc brakes, a RockShox Recon RL fork with 130mm of travel, a custom X-Fusion 02 Pro RL rear shock with 120mm of travel, and wide alloy wheels.
|FRAME||M5 alloy chassis and rear end, asymmetrical design, 29 Trail Geometry, threaded BB, fully enclosed internal cable routing, 12x148mm dropouts, sealed cartridge bearing pivots, replaceable derailleur hanger, 120mm of travel|
|FORK||RockShox Recon RL, Solo Air, 51mm offset, rebound adjust, lockout, 15x110mm Boost™ Maxle® Lite thru-axle, 130mm of travel|
|REAR SHOCK||X-Fusion 02 Pro RL, Rx Trail Tune, rebound adjust, lockout 190x42.5mm|
|FRONT HUB||Specialized, sealed cartridge bearings, 15x110mm spacing, 32h|
|REAR HUB||Specialized, sealed cartridge bearings, 12x148mm thru-axle, 32h|
|RIMS||Double-wall, 27mm internal width|
|INNER TUBES||Standard, Presta valve|
|FRONT TYRE||Butcher, GRID Casing, GRIPTON® compound, 2Bliss Ready, 29x2.3"|
|REAR TYRE||Purgatory, GRID casing, GRIPTON® compound, 2Bliss Ready, 29x2.3"|
|CRANKSET||SRAM NX, Boost™, direct-mount XSYNC, Powerspline|
|BOTTOM BRACKET||SRAM Power Spline|
|SHIFT LEVERS||Shimano SLX, 11-speed|
|REAR DERAILLEUR||Shimano SLX, Shadow Plus, GS cage, 11-speed|
|CASSETTE||Sunrace, ED Black, 11-speed, 11-46t|
|CHAIN||KMC X11, 11-speed w/ Missing Link™|
|FRONT BRAKE||Tektro Gemini Comp, hydraulic disc, resin pad, 200mm rotor|
|REAR BRAKE||Tektro Gemini Comp, hydraulic disc, resin pad, 180mm rotor|
|HANDLEBARS||Specialized, 6061 alloy, 6-degree upsweep, 8-degree backsweep, 27mm rise, 780mm width|
|GRIPS||Specialized Sip Grip, half-waffle|
|STEM||Specialized Trail, 3D forged alloy, 4-bolt, 7-degree rise|
|SADDLE||Body Geometry Henge Sport, steel rails, 143mm|
|SEATPOST||Alloy, two-bolt clamp, 34.9mm|
|SEAT BINDER||Alloy, 38.6mm|
|Bike Standover Height||750mm||756mm||769mm||770mm|
|Fork Length, Full||540mm||540mm||540mm||540mm|
|Head Tube Angle||67.5°||67.5°||67.5°||67.5°|
|Head Tube Length||100mm||100mm||125mm||140mm|
|Seat Tube Angle||75.8°||75.5°||75.1°||74.7°|
|Seat Tube Length||380mm||410mm||455mm||505mm|
|Top Tube Length, Horizontal||570mm||593mm||624mm||657mm|