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2025 Specialized Roubaix SL8 FACT 12R Carbon vs 2027 Trek Domane AL 4 Gen 4

The Trek Domane AL 4 Gen 4 size closest to your 54 is the 56. Compare the 56 instead

What changes on the Trek Domane AL 4 Gen 4

Compared with the Specialized Roubaix SL8 FACT 12R Carbon in 54, the Trek Domane AL 4 Gen 4 in 49 places the top of the head tube 45 mm lower and 13 mm further back, relative to the bottom bracket. Its wheelbase is 4 mm shorter, which can contribute to quicker direction changes.

Frame stack
−45 mm
Lower front end
Frame reach
−13 mm
Shorter frame reach
Wheelbase
−4 mm
Shorter: quicker to change direction
Head angle
−1.5°
Slacker: calmer steering
Chainstays
+5 mm
Longer: more planted

The two frames

2025 Specialized Roubaix SL8 FACT 12R Carbon (54) and 2027 Trek Domane AL 4 Gen 4 (49), lined up at the bottom bracketBoth frames drawn to scale. The Specialized Roubaix SL8 FACT 12R Carbon is drawn in full with its measurements, and the Trek Domane AL 4 Gen 4 is the colored outline on top.J 1005

Specialized Roubaix SL8 FACT 12R Carbon, 54Trek Domane AL 4 Gen 4, 49Drawn to scale and lined up at the bottom bracket.

Geometry side by side

MeasurementSpecialized Roubaix SL8 FACT 12R Carbon 54Trek Domane AL 4 Gen 4 49Difference
Reach381mm368−13 mm
Stack585mm540−45 mm
Head tube angle72.3°70.8−1.5°
Seat tube angle74°74.6+0.6°
Effective top tube550mm516−34 mm
Chainstay length420mm425+5 mm
Wheelbase1005mm1001−4 mm
BB drop78mm80+2 mm
BB height270mmnot listed
Standover766mm717−49 mm
Seat tube length465mm440−25 mm
Fork length375mmnot listed
Head tube length122mm123+1 mm

Differences are the Trek Domane AL 4 Gen 4 minus the Specialized Roubaix SL8 FACT 12R Carbon. Full charts: 2025 Specialized Roubaix SL8 FACT 12R Carbon, 2027 Trek Domane AL 4 Gen 4.

Where each sits in its class

Specialized Roubaix SL8 FACT 12R CarbonTrek Domane AL 4 Gen 4

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

Each bike is ranked against the other road 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 Roubaix SL8 FACT 12R CarbonS-Works SL8 FACT 12R CarbonTrek Domane AL 4 Gen 4Gen 4
ForkSpecialized Future Shock 3.3Trek Domane AL
SeatpostSpecialized S-Works Pave Seat postBontrager Comp
Framenot listedTrek Domane AL
Shifternot listedShimano Tiagra R4020
Derailleurnot listedShimano Tiagra R4000, Shimano Tiagra 4700
Cassettenot listedShimano RS400
Chainnot listedShimano LG500
Cranksetnot listedShimano Tiagra R4000
Chainringnot listedShimano Tiagra 4700
Bottom bracketnot listedShimano RS501
Wheelsetnot listedBontrager Paradigm 23
Tirenot listedBontrager Kwaremont
Hubnot listedFormula RX-142, Formula RX-512
Rimnot listedBontrager Paradigm 23
Rotornot listedShimano SM-RT66
Handlebarnot listedBontrager Comp
Stemnot listedBontrager Elite
Bar tapenot listedBontrager Supertack Perf
Headsetnot listedBontrager Expander Plug
Saddlenot listedTrek Verse Short

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