Quiver

2017 Specialized Sirrus Sport vs 2019 Trek FX Sport

The M is the Trek FX Sport size closest to your S Specialized Sirrus Sport. 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 Sport in S, the Trek FX Sport in M places the top of the head tube at about the same height and 9 mm further forward, relative to the bottom bracket.

Frame stack
±0 mm
About the same height
Frame reach
+9 mm
Longer frame reach
Wheelbase
+2 mm
About the same
Head angle
±0.0°
About the same head angle
Chainstays
−7 mm
Shorter: livelier

The two frames

2017 Specialized Sirrus Sport (S)The Specialized Sirrus Sport frame drawn to scale.J 1065

Only the Specialized Sirrus Sport is drawn. The Trek FX Sport numbers we have for size M are missing the seat angle.

Geometry side by side

MeasurementSpecialized Sirrus Sport STrek FX Sport MDifference
Reach394mm403+9 mm
Stack584mm584±0 mm
Head tube angle71°71.0°±0.0°
Seat tube angle73.3°not listed
Effective top tube570mm570±0 mm
Chainstay length445mm438−7 mm
Wheelbase1065mm1067+2 mm
BB drop70mm65−5 mm
BB height281mm285+4 mm
Standover750mm743−7 mm
Seat tube length440mm457+17 mm
Fork length410mmnot listed
Head tube length150mm160+10 mm

Differences are the Trek FX Sport minus the Specialized Sirrus Sport. Full charts: 2017 Specialized Sirrus Sport, 2019 Trek FX Sport.

Where each sits in its class

Specialized Sirrus SportTrek FX Sport

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

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.

PartSpecialized Sirrus SportSportTrek FX Sport4
DerailleurmicroSHIFT R9, Shimano AlivioShimano Tiagra, Shimano RD-4700 Tiagra
ChainKMC X9KMC X10
CranksetFSA VeroShimano R460
Bottom bracketSpecialized BB-7420STw/Boltsnot listed
TireSpecialized Nimbus ReflectBontrager AW1 Hard-Case Lite
BrakeShimano Acera M315Shimano MT201
SaddleSpecialized Canopy SportBontrager H1
Framenot listedTrek Alpha
Forknot listedTrek FX
Shifternot listedShimano Tiagra
Cassettenot listedShimano Tiagra
Handlebarnot listedBontrager Satellite Plus IsoZone
Seatpostnot listedBontrager SSR

Know what is on every bike.

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