2025 Specialized Stumpjumper 15 Alloy Features
Stumpjumper 15 Alloy is here to obliterate every trade-off in the trail game. Devour bumps like a big bike? Check. Short-travel control, playfulness, and efficiency? Double check. How about a heaping helping of personalization to make it perfect for the only rider who really matters—you?
Check, check, check.
KINEMATICS PERFECTED: As the quintessential trail bike, Stumpjumper 15 Alloy balances efficiency and optimal bump force management. For the anti-squat on Stumpjumper 15 Alloy, we struck a balance between the previous Stumpjumper and Stumpjumper EVO, as both had excellent pedaling characteristics.
HONED GEOMETRY: This bike’s 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.
RIDE YOUR WAY: The Stumpjumper 15 Alloy seamlessly integrates benchmark geo adjustability, making it the most personalizable trail bike ever. Six distinct geometry settings allow you to hone performance for any style and any terrain. The head angle and bottom bracket can be fine-tuned for stability or clearance.
FORM FOLLOWS FUN: We can make a frame as stiff as we want, but there’s such a thing as too stiff. To be one with the bike requires engineered compliance in the frame. We engineered the 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.
WHEEL SIZE: All coil-sprung models come with mixed wheels.
WHEEL CHOICE: With our aftermarket link shock links, you can choose between big wheels front and rear or mix things up with a 27.5” rear for a more responsive and playful ride. No matter what you choose, geometry is unaffected.
CARRY IT ALL: SWAT on Stumpjumper 15 elevates downtube storage, an innovation we pioneered.
MORE RELENTLESS THAN YOU: Our full-suspension bikes are built to be relentless, designed to endure years of hard riding, and backed by the best support and programs to keep you on the trail. Our unbeatable lifetime, no-questions-asked replacement suspension pivot bearings to the original owner is just one way we've got you covered.
At a Glance
- All-new M5 alloy frame with SWAT door integration
- Ride Dynamics tuned X-Fusion 02 Pro RL shock with adjustable rebound and lockout
- RockShox Psylo Silver fork with Motion Control Damper
- Reliable Shimano MT-420 4-piston brakes
- 12-speed Shimano Deore drivetrain
- Lifetime replacement of suspension pivot bearings to the original owner
Component Specifications
| Frame | M5 Alloy chassis and rear-end, Trail Geometry, SWAT™ Door integration, head tube angle adjustment, threaded BB, internal cable routing, 12x148mm dropouts, sealed cartridge bearing pivots, SRAM UDH compatible, 145mm of travel |
| Seat Binder | Alloy, 38.6mm |
| Fork | RockShox, Psylo Silver, Motion Control Damper, 15x110 axle, 44mm offset, S1:140mm of travel, S2-S6:150mm of travel |
| Rear Shock | X-Fusion 02 Pro RL, Ride Dynamics Trail Tune, rebound adjust, lockout S1:210x52.5mm, S2-S6:210x55mm |
| Shift Levers | Shimano Deore, M6100, 12spd |
| Rear Derailleur | Shimano Deore, M6100, 12pd, Shadow Plus |
| Cassette | Shimano Deore, M6100, 12spd w/Hyperglide+, 10-51t |
| Chain | Shimano Deore, M6100, 12-speed |
| Crankset | Shimano Deore, M6120, 30T ring, 55mm chainline, S1-S3:165mm, S4-S6: 170mm |
| Rims | Specialized Alloy, Tubeless Ready, 29mm internal width, 28h, Front: 29, Rear: S1-S2: 27.5, S3- S6: 29 |
| Front Hub | Alloy, sealed cartridge bearings, 15x110mm thru-axle, 28h |
| Rear Hub | Alloy, sealed cartridge bearings, 12x148mm thru-axle, 28h |
| Spokes | Stainless, 14g |
| Front Tire | Butcher, GRID TRAIL casing, GRIPTON® T9 compound, 2Bliss Ready, 29x2.3" |
| Rear Tire | Eliminator, GRID TRAIL casing, GRIPTON® T7 compound, 2Bliss Ready, S1-S2: 27.5x2.3, S3- S6: 29x2.3" |
| Inner Tubes | Standard, Presta valve |
| Front Brake | Shimano, BR-MT420, 4-piston caliper, hydraulic disc, 203mm |
| Rear Brake | Shimano, BR-MT420, 4-piston caliper, hydraulic disc, S1-S2: 180mm, S3-S6: 203mm |
| Stem | Alloy Trail Stem, 35mm bar bore |
| Handlebars | Specialized, 6000 series alloy, 6-degree upsweep, 8-degree backsweep. S1-S2: 780 width, 20mm rise: S3-S4: 800 width, 30mm rise: S5-S6: 800 width, 40mm rise |
| Grips | Specialized Trail Grips |
| Saddle | Bridge, Steel rails, S1-S2: 155mm, S3-S6: 143mm |
| Seatpost | TranzX Dropper, remote SLR LE lever, 34.9, S1: 125mm, S2: 150mm, S3: 170mm, S4-S6: 200mm |
2025 Specialized Stumpjumper 15 Alloy
| Bike/Frame Size | S1 | S2 | S3 | S4 | S5 | S6 |
|---|---|---|---|---|---|---|
| Stack | 608 mm | 618 mm | 627 mm | 640 mm | 654 mm | 667 mm |
| Reach | 400 mm | 425 mm | 450 mm | 475 mm | 500 mm | 530 mm |
| Chainstay Length | 430 mm | 432 mm | 435 mm | 435 mm | 445 mm | 445 mm |
| Wheelbase | 1149 mm | 1181 mm | 1213 mm | 1244 mm | 1285 mm | 1322 mm |
| Top-tube Length (horizontal) | 541 mm | 573 mm | 595 mm | 624 mm | 647 mm | 677 mm |
| Bike Standover Height | 738 mm | 751 mm | 745 mm | 745 mm | 745 mm | 751 mm |
| Seat Tube Length | 385 mm | 385 mm | 405 mm | 425 mm | 445 mm | 465 mm |
| Seat Tube Angle | 78° | 77° | 77° | 76.5° | 76.5° | 76.5° |
| Saddle Height for Effective ST Angle | 645 mm | 690 mm | 735 mm | 780 mm | 825 mm | 870 mm |
| Max Seatpost Insertion | 245 mm | 245 mm | 255 mm | 255 mm | 285 mm | 285 mm |
| Min Seatpost Insertion | 80 mm | 80 mm | 80 mm | 80 mm | 80 mm | 80 mm |
| Headtube Length | 95 mm | 100 mm | 110 mm | 125 mm | 140 mm | 155 mm |
| Headtube Angle | 64.5° | 64.5° | 64.5° | 64.5° | 64.5° | 64.5° |
| BB Height | 334 mm | 337 mm | 337 mm | 337 mm | 337 mm | 337 mm |
| BB Drop | 41 mm | 38 mm | 38 mm | 38 mm | 38 mm | 38 mm |
| Trail | 129 mm | 130 mm | 130 mm | 130 mm | 130 mm | 130 mm |
| Fork Length (full) | 551 mm | 561 mm | 561 mm | 561 mm | 561 mm | 561 mm |
| Fork Rake/Offset | 44 mm | 44 mm | 44 mm | 44 mm | 44 mm | 44 mm |
| Front Center | 720 mm | 751 mm | 780 mm | 812 mm | 843 mm | 879 mm |
Size Guide: 2025 Specialized Stumpjumper 15 Alloy
