Quiver

2023 Trek Session C 27.5 Frameset vs 2023 Specialized Demo Expert

The Specialized Demo Expert size closest to your M is the S2. Compare the S2 instead

What changes on the Specialized Demo Expert

Compared with the Trek Session C 27.5 Frameset in M, the Specialized Demo Expert in S4 places the top of the head tube 16 mm higher and 37 mm further forward, relative to the bottom bracket. Its wheelbase is 44 mm longer, which can contribute to stability at speed.

Frame stack
+16 mm
Higher front end
Frame reach
+37 mm
Longer frame reach
Wheelbase
+44 mm
Longer: steadier at speed
Head angle
−0.7°
Slacker: calmer steering
Chainstays
+3 mm
Longer: more planted

The two frames

We can't draw these frames yet. The Trek Session C 27.5 Frameset numbers we have for size M are missing the seat angle. The numbers below still compare.

Geometry side by side

MeasurementTrek Session C 27.5 Frameset MSpecialized Demo Expert S4Difference
Reach429466mm+37 mm
Stack616632mm+16 mm
Head tube angle63.5°62.8°−0.7°
Effective top tube584not listed
Chainstay length445448mm+3 mm
Wheelbase12351279mm+44 mm
BB drop20not listed
BB height356not listed
Standovernot listednot listed
Seat tube length425420mm−5 mm
Head tube length115105mm−10 mm
Seat tube anglenot listed76.8°

Differences are the Specialized Demo Expert minus the Trek Session C 27.5 Frameset. Full charts: 2023 Trek Session C 27.5 Frameset, 2023 Specialized Demo Expert.

Where each sits in its class

Trek Session C 27.5 FramesetSpecialized Demo Expert

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

Each bike is ranked against the other downhill 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.

PartTrek Session C 27.5 Frameset27.5 FramesetSpecialized Demo ExpertExpert
FrameTrek OCLVnot listed
HeadsetFSA Orbitnot listed
Forknot listedRockShox BoXXer 29
Rear shocknot listedRockShox Super Deluxe Select
Shifternot listedSRAM GX DH
Derailleurnot listedSRAM GX DH
Cassettenot listedSRAM GX DH
Chainnot listedSRAM PC1110
Cranksetnot listedSpecialized DESCENDANT DH
Bottom bracketnot listedSRAM DUB
Tirenot listedSpecialized Butcher
Brakenot listedSRAM Code RS
Stemnot listedSpecialized Descendant
Saddlenot listedSpecialized Henge DH

Know what is on every bike.

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