Quiver

2026 Specialized Stumpjumper 15 Pro vs 2026 Forbidden Heathen Framekit

The S1 is the Forbidden Heathen Framekit size closest to your S2 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 S2, the Forbidden Heathen Framekit in S1 places the top of the head tube at about the same height and 15 mm further forward, relative to the bottom bracket. Its wheelbase is 31 mm shorter, which can contribute to quicker direction changes.

Frame stack
±0 mm
About the same height
Frame reach
+15 mm
Longer frame reach
Wheelbase
−31 mm
Shorter: quicker to change direction
Head angle
±0.0°
About the same head angle
Chainstays
n/a
One of the bikes has no number for this

The two frames

2026 Specialized Stumpjumper 15 Pro (S2)The Specialized Stumpjumper 15 Pro frame drawn to scale.J 1186

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

MeasurementSpecialized Stumpjumper 15 Pro S2Forbidden Heathen Framekit S1Difference
Reach420435+15 mm
Stack621621±0 mm
Head tube angle6464±0.0°
Seat tube angle76.576−0.5°
Effective top tube574590+16 mm
Chainstay length432not listed
Wheelbase11861155.4−31 mm
BB drop35not listed
BB height340301−39 mm
Standover751716−35 mm
Seat tube length385400+15 mm
Head tube length10090−10 mm
Fork lengthnot listed541

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

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

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.

PartSpecialized Stumpjumper 15 ProProForbidden Heathen Framekit
FrameSpecialized Stumpjumper 15not listed
ForkFox 36 Factorynot listed
Rear shockFox Float X Factorynot listed
ShifterSRAM AXS POD Rockernot listed
DerailleurSRAM X0 Eagle Transmissionnot listed
CassetteSRAM 1295 X01not listed
CranksetSRAM X0 Eagle Transmissionnot listed
ChainringSRAM 32not listed
Bottom bracketSRAM DUB GXnot listed
WheelsetRoval Traverse SL IInot listed
TireSpecialized Butcher, Specialized Eliminatornot listed
BrakeSRAM Maven Silver Stealthnot listed
RotorSRAM CenterLinenot listed
HandlebarDeity Speedwaynot listed
Dropper postBikeYoke Revive Max 3.0not listed
SaddleSpecialized Bridge Expertnot listed

Know what is on every bike.

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