2025 Trek Domane AL 4 Gen 4 vs 2025 Specialized Roubaix SL8 Pro
The 54 is the Specialized Roubaix SL8 Pro size closest to your 56 Trek Domane AL 4 Gen 4. 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 Specialized Roubaix SL8 Pro
Compared with the Trek Domane AL 4 Gen 4 in 56, the Specialized Roubaix SL8 Pro in 54 places the top of the head tube 6 mm lower and 4 mm further forward, relative to the bottom bracket. Its wheelbase is 13 mm shorter, which can contribute to quicker direction changes.
- Frame stack
- −6 mm
- Lower front end
- Frame reach
- +4 mm
- Longer frame reach
- Wheelbase
- −13 mm
- Shorter: quicker to change direction
- Head angle
- +0.4°
- Steeper: sharper steering
- Chainstays
- ±0 mm
- About the same
The two frames
We can't draw these frames yet. The Trek Domane AL 4 Gen 4 numbers we have for size 56 are missing the seat angle. The numbers below still compare.
Geometry side by side
| Measurement | Trek Domane AL 4 Gen 4 56 | Specialized Roubaix SL8 Pro 54 | Difference |
|---|---|---|---|
| Reach | 377 | 381mm | +4 mm |
| Stack | 591 | 585mm | −6 mm |
| Head tube angle | 71.9° | 72.3° | +0.4° |
| Effective top tube | 554 | not listed | |
| Chainstay length | 420 | 420mm | ±0 mm |
| Wheelbase | 1018 | 1005mm | −13 mm |
| BB drop | 78 | 78mm | ±0 mm |
| Standover | 776 | 766mm | −10 mm |
| Seat tube length | 525 | 465mm | −60 mm |
| Head tube length | 175 | 122mm | −53 mm |
| Seat tube angle | not listed | 74° | |
| BB height | not listed | 270mm | |
| Fork length | not listed | 375mm |
Differences are the Specialized Roubaix SL8 Pro minus the Trek Domane AL 4 Gen 4. Full charts: 2025 Trek Domane AL 4 Gen 4, 2025 Specialized Roubaix SL8 Pro.
Where each sits in its class
Trek Domane AL 4 Gen 4Specialized Roubaix SL8 Pro
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.
| Part | Trek Domane AL 4 Gen 4Gen 4 | Specialized Roubaix SL8 ProSL8 Pro |
|---|---|---|
| Frame | Trek Domane AL | not listed |
| Fork | Trek Domane AL | Specialized Future Shock 3.3 |
| Shifter | Shimano Tiagra | Shimano Ultegra R8170 Di2 |
| Derailleur | Shimano Tiagra | Shimano Ultegra R8150 Di2 |
| Cassette | Shimano HG500 | Shimano Ultegra |
| Chain | Shimano HG54 Tiagra | Shimano XT M8100 |
| Crankset | Shimano Tiagra | Shimano Ultegra R8100 |
| Chainring | Shimano Tiagra | not listed |
| Bottom bracket | Shimano RS501 | not listed |
| Wheelset | Bontrager Paradigm 23 | Roval Terra CL II |
| Tire | Bontrager Kwaremont Comp | Specialized S-Works Mondo 2BR |
| Hub | Formula RX-512, Formula RX-142 | not listed |
| Rim | Bontrager Paradigm SL | not listed |
| Brake | Shimano Tiagra | Shimano Ultegra |
| Rotor | Shimano SM-RT66 | not listed |
| Handlebar | Bontrager Comp | not listed |
| Stem | Bontrager Elite | Specialized Future |
| Bar tape | Bontrager Supertack Performance | not listed |
| Seatpost | Bontrager Comp | Specialized S-Works Pave Seat post |
| Saddle | Bontrager Verse Short | Specialized Power Pro Mirror |
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