Quiver

2017 Specialized Sirrus vs 2019 Trek FX Sport

The L is the Trek FX Sport size closest to your M Specialized Sirrus. 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 in M, the Trek FX Sport in L places the top of the head tube 11 mm higher and 7 mm further forward, relative to the bottom bracket.

Frame stack
+11 mm
Higher front end
Frame reach
+7 mm
Longer frame reach
Wheelbase
−1 mm
About the same
Head angle
±0.0°
About the same head angle
Chainstays
−7 mm
Shorter: livelier

The two frames

2017 Specialized Sirrus (M)The Specialized Sirrus frame drawn to scale.J 1073

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

Geometry side by side

MeasurementSpecialized Sirrus MTrek FX Sport LDifference
Reach402mm409+7 mm
Stack600mm611+11 mm
Head tube angle71.5°71.5°±0.0°
Seat tube angle73.5°not listed
Effective top tube580mm590+10 mm
Chainstay length445mm438−7 mm
Wheelbase1073mm1072−1 mm
BB drop70mm65−5 mm
BB height281mm285+4 mm
Standover786mm781−5 mm
Seat tube length485mm508+23 mm
Fork length410mmnot listed
Head tube length165mm185+20 mm

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

Where each sits in its class

Specialized SirrusTrek 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 SirrusSirrusTrek FX Sport4
ShifterShimano EF500Shimano Tiagra
DerailleurShimano Tourney, Shimano AltusShimano Tiagra, Shimano RD-4700 Tiagra
ChainKMC X8KMC X10
CranksetSpecialized StoutShimano R460
TireSpecialized Nimbus ReflectBontrager AW1 Hard-Case Lite
SaddleSpecialized Canopy SportBontrager H1
Framenot listedTrek Alpha
Forknot listedTrek FX
Cassettenot listedShimano Tiagra
Brakenot listedShimano MT201
Handlebarnot listedBontrager Satellite Plus IsoZone
Seatpostnot listedBontrager SSR

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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