2017 Specialized Sirrus Expert Carbon vs 2019 Trek FX Sport
The M is the Trek FX Sport size closest to your M Specialized Sirrus Expert Carbon. 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 FX Sport
Compared with the Specialized Sirrus Expert Carbon in M, the Trek FX Sport in M places the top of the head tube 7 mm lower and about as far forward, relative to the bottom bracket. Its wheelbase is 7 mm longer, which can contribute to stability at speed.
- Frame stack
- −7 mm
- Lower front end
- Frame reach
- ±0 mm
- About the same reach
- Wheelbase
- +7 mm
- Longer: steadier at speed
- Head angle
- −0.5°
- Slacker: calmer steering
- Chainstays
- +3 mm
- Longer: more planted
The two frames
Only the Specialized Sirrus Expert Carbon is drawn. The Trek FX Sport numbers we have for size M are missing the seat angle.
Geometry side by side
| Measurement | Specialized Sirrus Expert Carbon M | Trek FX Sport M | Difference |
|---|---|---|---|
| Reach | 403mm | 403 | ±0 mm |
| Stack | 591mm | 584 | −7 mm |
| Head tube angle | 71.5° | 71.0° | −0.5° |
| Seat tube angle | 73.5° | not listed | |
| Effective top tube | 578mm | 570 | −8 mm |
| Chainstay length | 435mm | 438 | +3 mm |
| Wheelbase | 1060mm | 1067 | +7 mm |
| BB drop | 70mm | 65 | −5 mm |
| BB height | 275mm | 285 | +10 mm |
| Standover | 784.6mm | 743 | −42 mm |
| Seat tube length | 485mm | 457 | −28 mm |
| Fork length | 398mm | not listed | |
| Head tube length | 165mm | 160 | −5 mm |
Differences are the Trek FX Sport minus the Specialized Sirrus Expert Carbon. Full charts: 2017 Specialized Sirrus Expert Carbon, 2019 Trek FX Sport.
Where each sits in its class
Specialized Sirrus Expert CarbonTrek FX Sport
Each bike is ranked against the other commuter 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 Sirrus Expert CarbonExpert Carbon | Trek FX Sport4 |
|---|---|---|
| Derailleur | Shimano 105 | Shimano Tiagra, Shimano RD-4700 Tiagra |
| Cassette | Shimano 105 | Shimano Tiagra |
| Chain | KMC X11-1 | KMC X10 |
| Crankset | FSA Gossamer Pro | Shimano R460 |
| Bottom bracket | Specialized BB386 Evo | not listed |
| Wheelset | Specialized Axis Expert | not listed |
| Tire | Specialized Espoir Sport Reflect | Bontrager AW1 Hard-Case Lite |
| Brake | Shimano Deore | Shimano MT201 |
| Stem | Specialized Flowset | not listed |
| Seatpost | Specialized CG-R | Bontrager SSR |
| Saddle | Specialized Canopy Comp | Bontrager H1 |
| Frame | not listed | Trek Alpha |
| Fork | not listed | Trek FX |
| Shifter | not listed | Shimano Tiagra |
| Handlebar | not listed | Bontrager Satellite Plus IsoZone |
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