Quiver

2023 Specialized Demo Expert vs 2023 Trek Session C 27.5 Frameset

The M is the Trek Session C 27.5 Frameset size closest to your S2 Specialized Demo Expert. 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 Trek Session C 27.5 Frameset

Compared with the Specialized Demo Expert in S2, the Trek Session C 27.5 Frameset in M places the top of the head tube 16 mm lower and 3 mm further forward, relative to the bottom bracket. Its wheelbase is 4 mm shorter, which can contribute to quicker direction changes.

Frame stack
−16 mm
Lower front end
Frame reach
+3 mm
Longer frame reach
Wheelbase
−4 mm
Shorter: quicker to change direction
Head angle
+0.7°
Steeper: sharper steering
Chainstays
−3 mm
Shorter: livelier

The two frames

2023 Specialized Demo Expert (S2)The Specialized Demo Expert frame drawn to scale.J 1239

Only the Specialized Demo Expert is drawn. The Trek Session C 27.5 Frameset numbers we have for size M are missing the seat angle.

Geometry side by side

MeasurementSpecialized Demo Expert S2Trek Session C 27.5 Frameset MDifference
Reach426mm429+3 mm
Stack632mm616−16 mm
Head tube angle62.8°63.5°+0.7°
Seat tube angle78.2°not listed
Chainstay length448mm445−3 mm
Wheelbase1239mm1235−4 mm
Seat tube length394mm425+31 mm
Head tube length105mm115+10 mm
Effective top tubenot listed584
BB dropnot listed20
BB heightnot listed356
Standovernot listednot listed

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

Where each sits in its class

Specialized Demo ExpertTrek Session C 27.5 Frameset

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.

PartSpecialized Demo ExpertExpertTrek Session C 27.5 Frameset27.5 Frameset
ForkRockShox BoXXer 29not listed
Rear shockRockShox Super Deluxe Selectnot listed
ShifterSRAM GX DHnot listed
DerailleurSRAM GX DHnot listed
CassetteSRAM GX DHnot listed
ChainSRAM PC1110not listed
CranksetSpecialized DESCENDANT DHnot listed
Bottom bracketSRAM DUBnot listed
TireSpecialized Butchernot listed
BrakeSRAM Code RSnot listed
StemSpecialized Descendantnot listed
SaddleSpecialized Henge DHnot listed
Framenot listedTrek OCLV
Headsetnot listedFSA Orbit

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