Quiver

2017 Specialized Demo FSR LTD 650B vs 2015 Trek Session DH 27.5

The L is the Trek Session DH 27.5 size closest to your LONG Specialized Demo FSR LTD 650B. 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 FSR LTD 650B in LONG, the Trek Session DH 27.5 in L places the top of the head tube 11 mm lower and 8 mm further back, relative to the bottom bracket.

Frame stack
−11 mm
Lower front end
Frame reach
−8 mm
Shorter frame reach
Wheelbase
+1 mm
About the same
Head angle
+0.7°
Steeper: sharper steering
Chainstays
+13 mm
Longer: more planted

The two frames

2017 Specialized Demo FSR LTD 650B (LONG)The Specialized Demo FSR LTD 650B frame drawn to scale.J 1228

Only the Specialized Demo FSR LTD 650B is drawn. The Trek Session DH 27.5 numbers we have for size L are missing the seat angle.

Geometry side by side

MeasurementSpecialized Demo FSR LTD 650B LONGTrek Session DH 27.5 LDifference
Reach440mm432−8 mm
Stack614mm603−11 mm
Head tube angle63.5°64.2°+0.7°
Seat tube angle74°not listed
Effective top tube616mm614−2 mm
Chainstay length430mm443+13 mm
Wheelbase1228mm1229+1 mm
BB drop12mm14+2 mm
BB height342mm364+22 mm
Standover698mm790+92 mm
Seat tube length367mm390+23 mm
Head tube length105mm115+10 mm

Differences are the Trek Session DH 27.5 minus the Specialized Demo FSR LTD 650B. Full charts: 2017 Specialized Demo FSR LTD 650B, 2015 Trek Session DH 27.5.

Where each sits in its class

Specialized Demo FSR LTD 650BTrek 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 Demo FSR LTD 650B8 FSR LTD 650BTrek Session DH 27.588 DH 27.5
Rear shockÖhlins TTXnot listed
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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