Product Info
Details + Specs
2025 Stumpjumper 15 Comp Alloy
One trail bike, fewer compromises
The Stumpjumper 15 Alloy combines the bump-eating capability of a bigger bike with the control, playfulness and efficiency expected from a modern trail bike. GENIE suspension, adjustable geometry and wheel-size flexibility let riders tune it for local trails or harder all-mountain days.
Best for: Technical trail riding, all-mountain days and riders who want adjustable handling.
At a glance
Frame
M5 alloy, 145 mm travel
Fork
FOX 36 Rhythm, 140-150 mm
Shock
FOX FLOAT Performance GENIE
Drivetrain
Shimano SLX 12-speed
Brakes
TRP Trail EVO 4-piston
Weight
16.17 kg in size S4
Key highlights
GENIE air-spring technology blends supple traction, bottom-out resistance and independent support tuning.
Six geometry settings plus 29-inch or mixed-wheel compatibility let riders tune handling to terrain.
FOX 36 Rhythm suspension, Shimano SLX 12-speed shifting and TRP four-piston brakes form a durable trail build.
SWAT downtube storage and an X-Fusion Manic dropper add practical trail-ready function.
Complete specification
Full build details
Components are grouped by bike system so the complete build is easy to scan.
Frameset
Frame
M5 alloy chassis and rear end, Trail Geometry, SWAT Door, head-angle adjustment, threaded bottom bracket, internal routing, 12x148 mm dropouts, sealed pivot bearings, SRAM UDH compatibility and 145 mm travel
Seat binder
Alloy, 38.6 mm
Suspension
Rear shock
FOX FLOAT Performance with Specialized GENIE Shock Tech, Ride Dynamics Trail Tune, 2-position lever and low-speed rebound adjustment; S1: 210x52.5 mm, S2-S6: 210x55 mm
Fork
FOX FLOAT 36 Rhythm, GRIP damper, 2-position Sweep adjustment, 15x110 mm axle and 44 mm offset; S1: 140 mm travel, S2-S6: 150 mm travel
Brakes
Front brake
TRP Trail EVO, 4-piston hydraulic disc, 203 mm rotor
Rear brake
TRP Trail EVO, 4-piston hydraulic disc; S1-S2: 180 mm rotor, S3-S6: 203 mm rotor
Drivetrain
Shift levers
Shimano SLX M7100, 12-speed
Rear derailleur
Shimano SLX M7100 SGS, 12-speed
Cassette
Shimano SLX CS-M7100, 12-speed, 10-51t
Chain
Shimano SLX M7100, 12-speed
Crankset
Shimano SLX M7120, 32T, 55 mm chainline; S1-S3: 165 mm, S4-S6: 170 mm
Bottom bracket
Shimano BB-MT801, threaded
Wheels and tyres
Rims
Specialized hookless alloy, 30 mm internal width, tubeless ready; 29-inch front, S1-S2 27.5-inch rear, S3-S6 29-inch rear
Front hub
Specialized alloy, sealed cartridge bearings, 6-bolt, 15x110 mm thru-axle, 32h
Rear hub
Alloy, sealed cartridge bearings, 12x148 mm thru-axle, 28h
Spokes
DT Swiss Industry
Front tyre
Butcher GRID TRAIL, GRIPTON T9, 2Bliss Ready, 29x2.3
Rear tyre
Eliminator GRID TRAIL, GRIPTON T7, 2Bliss Ready; S1-S2: 27.5x2.3, S3-S6: 29x2.3
Inner tubes
Standard, Presta valve
Cockpit and contact points
Stem
Alloy Trail Stem, 35 mm bar bore
Handlebars
Specialized 6000-series alloy, 6-degree upsweep and 8-degree backsweep; size-specific width and rise
Grips
Specialized Trail Grips
Saddle
Bridge Comp with hollow Cr-Mo rails; S1-S2: 155 mm, S3-S6: 143 mm
Seatpost
X-Fusion Manic, internally routed with remote; S1: 125 mm, S2: 150 mm, S3: 170 mm, S4-S6: 190 mm
Storage, weight and sizing
Storage
SWAT internal downtube storage
Weight
16.17 kg (35 lb, 10.4 oz)
Reference size
S4
Weight is based on a production painted bike in the stated reference size. Actual weight can vary with colour, size and component variation. Specifications are subject to change without notice.