2015 Specialized Fatboy SL vs 2015 Trek Farley
The M is the Trek Farley size closest to your M Specialized Fatboy SL. 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 Farley
Compared with the Specialized Fatboy SL in M, the Trek Farley in M places the top of the head tube 5 mm lower and 9 mm further back, relative to the bottom bracket. Its wheelbase is 15 mm shorter, which can contribute to quicker direction changes.
- Frame stack
- −5 mm
- Lower front end
- Frame reach
- −9 mm
- Shorter frame reach
- Wheelbase
- −15 mm
- Shorter: quicker to change direction
- Head angle
- −0.5°
- Slacker: calmer steering
- Chainstays
- −15 mm
- Shorter: livelier
The two frames
Only the Specialized Fatboy SL is drawn. The Trek Farley numbers we have for size M are missing the seat angle.
Geometry side by side
| Measurement | Specialized Fatboy SL M | Trek Farley M | Difference |
|---|---|---|---|
| Reach | 420mm | 411 | −9 mm |
| Stack | 600mm | 595 | −5 mm |
| Head tube angle | 70.5° | 70.0° | −0.5° |
| Seat tube angle | 73° | not listed | |
| Effective top tube | 603mm | 593 | −10 mm |
| Chainstay length | 455mm | 440 | −15 mm |
| Wheelbase | 1105mm | 1090 | −15 mm |
| BB drop | 60mm | 55 | −5 mm |
| BB height | 315mm | 313 | −2 mm |
| Standover | 793mm | 782 | −11 mm |
| Seat tube length | 445mm | 419 | −26 mm |
| Head tube length | 120mm | 100 | −20 mm |
Differences are the Trek Farley minus the Specialized Fatboy SL. Full charts: 2015 Specialized Fatboy SL, 2015 Trek Farley.
Where each sits in its class
Specialized Fatboy SLTrek Farley
Each bike is ranked against the other fat 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 | Specialized Fatboy SLSL | Trek Farley6 |
|---|---|---|
| Shifter | SRAM XX1 | Shimano Deore |
| Derailleur | SRAM XX1 | SRAM X-5, Shimano Deore XT |
| Cassette | SRAM XX1 | Shimano HG50 |
| Chain | KMC X11L | KMC X10 |
| Crankset | Race Face Next SL | not listed |
| Tire | Specialized Ground Control Fat | Bontrager Hodag |
| Hub | Specialized Stout XC 135, Specialized Stout XC 190 | not listed |
| Rim | Hed Big Deal | Sun Ringlé Mulefüt |
| Brake | Magura MT8 | Avid DB 1 |
| Stem | Specialized Stout XC | not listed |
| Grips | Specialized Sip Grip | not listed |
| Saddle | Specialized Phenom Expert | Bontrager Evoke 2 |
| Frame | not listed | Trek Alpha Platinum |
| Headset | not listed | FSA IS2 |
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