2017 Trek Session DH 27.5 vs 2018 Specialized Demo 8 Frameset
The Specialized Demo 8 Frameset size closest to your M is the M. Compare the M instead
What changes on the Specialized Demo 8 Frameset
Compared with the Trek Session DH 27.5 in M, the Specialized Demo 8 Frameset in SHORT places the top of the head tube 11 mm higher and 13 mm further back, relative to the bottom bracket. Its wheelbase is 22 mm shorter, which can contribute to quicker direction changes.
- Frame stack
- +11 mm
- Higher front end
- Frame reach
- −13 mm
- Shorter frame reach
- Wheelbase
- −22 mm
- Shorter: quicker to change direction
- Head angle
- −0.7°
- Slacker: calmer steering
- Chainstays
- −13 mm
- Shorter: livelier
The two frames
We can't draw these frames yet. The Trek Session DH 27.5 numbers we have for size M are missing the seat angle. The numbers below still compare.
Geometry side by side
| Measurement | Trek Session DH 27.5 M | Specialized Demo 8 Frameset SHORT | Difference |
|---|---|---|---|
| Reach | 408 | 395mm | −13 mm |
| Stack | 603 | 614mm | +11 mm |
| Head tube angle | 64.2° | 63.5° | −0.7° |
| Effective top tube | 590 | 571mm | −19 mm |
| Chainstay length | 443 | 430mm | −13 mm |
| Wheelbase | 1205 | 1183mm | −22 mm |
| BB drop | 9 | 12mm | +3 mm |
| BB height | 364 | 342mm | −22 mm |
| Standover | 793 | 698mm | −95 mm |
| Seat tube length | 426 | 367mm | −59 mm |
| Head tube length | 115 | 105mm | −10 mm |
| Seat tube angle | not listed | 74° | |
| Fork length | not listed | 590mm |
Differences are the Specialized Demo 8 Frameset minus the Trek Session DH 27.5. Full charts: 2017 Trek Session DH 27.5, 2018 Specialized Demo 8 Frameset.
Where each sits in its class
Trek Session DH 27.5Specialized Demo 8 Frameset
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.
| Part | Trek Session DH 27.588 DH 27.5 | Specialized Demo 8 FramesetS-Works Frameset |
|---|---|---|
| Frame | Trek Alpha Platinum | not listed |
| Fork | RockShox BoXXer RC | not listed |
| Shifter | SRAM X0 DH | not listed |
| Derailleur | SRAM X01 | not listed |
| Cassette | SRAM GX DH | not listed |
| Chain | SRAM PC1110 | not listed |
| Crankset | TruVativ Descendant | not listed |
| Pedals | Wellgo MG-1 | not listed |
| Wheelset | DT Swiss FR2150 | not listed |
| Tire | Bontrager G4 Team Issue | not listed |
| Brake | SRAM Code R | not listed |
| Handlebar | Bontrager Line | not listed |
| Stem | Race Face Chester | not listed |
| Headset | FSA Orbit | not listed |
| Seatpost | Bontrager Rhythm Elite | not listed |
| Saddle | Bontrager Evoke 2 | not listed |
| Rear shock | not listed | Öhlins TTX |
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