Quiver

2026 Forbidden Heathen Framekit vs 2026 Specialized Stumpjumper 15 Pro

The Specialized Stumpjumper 15 Pro size closest to your S2 is the S3. Compare the S3 instead

What changes on the Specialized Stumpjumper 15 Pro

Compared with the Forbidden Heathen Framekit in S2, the Specialized Stumpjumper 15 Pro in S4 places the top of the head tube 14 mm higher and 15 mm further forward, relative to the bottom bracket. Its wheelbase is 56 mm longer, which can contribute to stability at speed.

Frame stack
+14 mm
Higher front end
Frame reach
+15 mm
Longer frame reach
Wheelbase
+56 mm
Longer: steadier at speed
Head angle
±0.0°
About the same head angle
Chainstays
n/a
One of the bikes has no number for this

The two frames

We can't draw these frames yet. The Forbidden Heathen Framekit numbers we have for size S2 are missing the chainstay length. The numbers below still compare.

Geometry side by side

MeasurementForbidden Heathen Framekit S2Specialized Stumpjumper 15 Pro S4Difference
Reach455470+15 mm
Stack630644+14 mm
Head tube angle6464±0.0°
Seat tube angle7676±0.0°
Effective top tube612625+13 mm
Wheelbase1192.81249+56 mm
BB height301340+39 mm
Standover728745+17 mm
Seat tube length420425+5 mm
Fork length541not listed
Head tube length100125+25 mm
Chainstay lengthnot listed435
BB dropnot listed35

Differences are the Specialized Stumpjumper 15 Pro minus the Forbidden Heathen Framekit. Full charts: 2026 Forbidden Heathen Framekit, 2026 Specialized Stumpjumper 15 Pro.

Where each sits in its class

Forbidden Heathen FramekitSpecialized Stumpjumper 15 Pro

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.

PartForbidden Heathen FramekitSpecialized Stumpjumper 15 ProPro
Framenot listedSpecialized Stumpjumper 15
Forknot listedFox 36 Factory
Rear shocknot listedFox Float X Factory
Shifternot listedSRAM AXS POD Rocker
Derailleurnot listedSRAM X0 Eagle Transmission
Cassettenot listedSRAM 1295 X01
Cranksetnot listedSRAM X0 Eagle Transmission
Chainringnot listedSRAM 32
Bottom bracketnot listedSRAM DUB GX
Wheelsetnot listedRoval Traverse SL II
Tirenot listedSpecialized Butcher, Specialized Eliminator
Brakenot listedSRAM Maven Silver Stealth
Rotornot listedSRAM CenterLine
Handlebarnot listedDeity Speedway
Dropper postnot listedBikeYoke Revive Max 3.0
Saddlenot listedSpecialized Bridge Expert

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