Quiver

2016 Specialized Demo vs 2015 Trek Session DH 27.5

The M is the Trek Session DH 27.5 size closest to your M Specialized Demo. 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 DH 27.5

Compared with the Specialized Demo in M, the Trek Session DH 27.5 in M places the top of the head tube 11 mm lower and 12 mm further back, relative to the bottom bracket. Its wheelbase is 3 mm shorter, which can contribute to quicker direction changes.

Frame stack
−11 mm
Lower front end
Frame reach
−12 mm
Shorter frame reach
Wheelbase
−3 mm
Shorter: quicker to change direction
Head angle
+0.7°
Steeper: sharper steering
Chainstays
+13 mm
Longer: more planted

The two frames

2016 Specialized Demo (M)The Specialized Demo frame drawn to scale.J 1208

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

Geometry side by side

MeasurementSpecialized Demo MTrek Session DH 27.5 MDifference
Reach420408−12 mm
Stack614603−11 mm
Head tube angle63.564.2°+0.7°
Seat tube angle74not listed
Effective top tube596590−6 mm
Chainstay length430443+13 mm
Wheelbase12081205−3 mm
BB drop1214+2 mm
BB height342364+22 mm
Standover698793+95 mm
Seat tube length394390−4 mm
Head tube length105115+10 mm

Differences are the Trek Session DH 27.5 minus the Specialized Demo. Full charts: 2016 Specialized Demo, 2015 Trek Session DH 27.5.

Where each sits in its class

Specialized DemoTrek Session DH 27.5

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 DemoTrek Session DH 27.588 DH 27.5
Framenot listedTrek Alpha Platinum
Forknot listedRockShox BoXXer
Shifternot listedSRAM X9
Derailleurnot listedSRAM X-0
Cassettenot listedSRAM PG-1050
Chainnot listedKMC X10
Cranksetnot listedTruVativ Descendant DH
Pedalsnot listedWellgo MG-1
Wheelsetnot listedDT Swiss FR2150
Tirenot listedBontrager G4 Team Issue
Brakenot listedAvid Code
Handlebarnot listedBontrager Rhythm Elite
Stemnot listedBontrager Rhythm
Headsetnot listedFSA NO.57E
Seatpostnot listedBontrager Rhythm Elite
Saddlenot listedBontrager Evoke 2

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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