Quiver

2018 Specialized Demo 8 Frameset vs 2020 Trek Session C 27.5 Frameset

The L is the Trek Session C 27.5 Frameset size closest to your EXTRA LONG Specialized Demo 8 Frameset. 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 8 Frameset in EXTRA LONG, the Trek Session C 27.5 Frameset in L places the top of the head tube at about the same height and 10 mm further back, relative to the bottom bracket. Its wheelbase is 8 mm longer, which can contribute to stability at speed.

Frame stack
+2 mm
About the same height
Frame reach
−10 mm
Shorter frame reach
Wheelbase
+8 mm
Longer: steadier at speed
Head angle
±0.0°
About the same head angle
Chainstays
+15 mm
Longer: more planted

The two frames

2018 Specialized Demo 8 Frameset (EXTRA LONG)The Specialized Demo 8 Frameset frame drawn to scale.J 1248

Only the Specialized Demo 8 Frameset is drawn. The Trek Session C 27.5 Frameset numbers we have for size L are missing the seat angle.

Geometry side by side

MeasurementSpecialized Demo 8 Frameset EXTRA LONGTrek Session C 27.5 Frameset LDifference
Reach460mm450−10 mm
Stack614mm616+2 mm
Head tube angle63.5°63.5°±0.0°
Seat tube angle74°not listed
Effective top tube636mm606−30 mm
Chainstay length430mm445+15 mm
Wheelbase1248mm1256+8 mm
BB drop12mm20+8 mm
BB height342mm356+14 mm
Standover698mm746+48 mm
Seat tube length367mm456+89 mm
Fork length590mmnot listed
Head tube length105mm115+10 mm

Differences are the Trek Session C 27.5 Frameset minus the Specialized Demo 8 Frameset. Full charts: 2018 Specialized Demo 8 Frameset, 2020 Trek Session C 27.5 Frameset.

Where each sits in its class

Specialized Demo 8 FramesetTrek 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 8 FramesetS-Works FramesetTrek Session C 27.5 Frameset27.5 Frameset
Rear shockÖhlins TTXnot listed
Framenot listedTrek OCLV
Headsetnot listedFSA Orbit

Know what is on every bike.

Add your bike to Quiver. Keep its parts, setup, and service history together, then share your build.

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