2026 Specialized Stumpjumper 15 Pro vs 2026 Forbidden Heathen Framekit
The S1 is the Forbidden Heathen Framekit size closest to your S1 Specialized Stumpjumper 15 Pro. We match frame stack and reach. This is a geometry comparison, not a fit recommendation; stem, spacers, handlebars and saddle setup also affect your riding position.
What changes on the Forbidden Heathen Framekit
Compared with the Specialized Stumpjumper 15 Pro in S1, the Forbidden Heathen Framekit in S1 places the top of the head tube 10 mm higher and 35 mm further forward, relative to the bottom bracket.
- Frame stack
- +10 mm
- Higher front end
- Frame reach
- +35 mm
- Longer frame reach
- Wheelbase
- +2 mm
- About the same
- Head angle
- ±0.0°
- About the same head angle
- Chainstays
- n/a
- One of the bikes has no number for this
The two frames
Only the Specialized Stumpjumper 15 Pro is drawn. The Forbidden Heathen Framekit numbers we have for size S1 are missing the chainstay length.
Geometry side by side
| Measurement | Specialized Stumpjumper 15 Pro S1 | Forbidden Heathen Framekit S1 | Difference |
|---|---|---|---|
| Reach | 400 | 435 | +35 mm |
| Stack | 611 | 621 | +10 mm |
| Head tube angle | 64 | 64 | ±0.0° |
| Seat tube angle | 77.7 | 76 | −1.7° |
| Effective top tube | 542 | 590 | +48 mm |
| Chainstay length | 430 | not listed | |
| Wheelbase | 1153 | 1155.4 | +2 mm |
| BB drop | 38 | not listed | |
| BB height | 337 | 301 | −36 mm |
| Standover | 738 | 716 | −22 mm |
| Seat tube length | 385 | 400 | +15 mm |
| Head tube length | 95 | 90 | −5 mm |
| Fork length | not listed | 541 |
Differences are the Forbidden Heathen Framekit minus the Specialized Stumpjumper 15 Pro. Full charts: 2026 Specialized Stumpjumper 15 Pro, 2026 Forbidden Heathen Framekit.
Where each sits in its class
Specialized Stumpjumper 15 ProForbidden Heathen Framekit
Each bike is ranked against the other trail bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.
What each ships with
The stock build of each bike's first listed trim. Parts that match are dimmed.
| Part | Specialized Stumpjumper 15 ProPro | Forbidden Heathen Framekit |
|---|---|---|
| Frame | Specialized Stumpjumper 15 | not listed |
| Fork | Fox 36 Factory | not listed |
| Rear shock | Fox Float X Factory | not listed |
| Shifter | SRAM AXS POD Rocker | not listed |
| Derailleur | SRAM X0 Eagle Transmission | not listed |
| Cassette | SRAM 1295 X01 | not listed |
| Crankset | SRAM X0 Eagle Transmission | not listed |
| Chainring | SRAM 32 | not listed |
| Bottom bracket | SRAM DUB GX | not listed |
| Wheelset | Roval Traverse SL II | not listed |
| Tire | Specialized Butcher, Specialized Eliminator | not listed |
| Brake | SRAM Maven Silver Stealth | not listed |
| Rotor | SRAM CenterLine | not listed |
| Handlebar | Deity Speedway | not listed |
| Dropper post | BikeYoke Revive Max 3.0 | not listed |
| Saddle | Specialized Bridge Expert | not listed |
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