2025 Specialized Aethos Pro Shimano vs 2025 Trek Émonda ALR
The 54 is the Trek Émonda ALR size closest to your 54 Specialized Aethos Pro Shimano. 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 Émonda ALR
Compared with the Specialized Aethos Pro Shimano in 54, the Trek Émonda ALR in 54 places the top of the head tube 3 mm lower and about as far forward, relative to the bottom bracket. Its wheelbase is 3 mm longer, which can contribute to stability at speed.
- Frame stack
- −3 mm
- Lower front end
- Frame reach
- +2 mm
- About the same reach
- Wheelbase
- +3 mm
- Longer: steadier at speed
- Head angle
- ±0.0°
- About the same head angle
- Chainstays
- ±0 mm
- About the same
The two frames
Only the Specialized Aethos Pro Shimano is drawn. The Trek Émonda ALR numbers we have for size 54 are missing the seat angle.
Geometry side by side
| Measurement | Specialized Aethos Pro Shimano 54 | Trek Émonda ALR 54 | Difference |
|---|---|---|---|
| Reach | 384mm | 386 | +2 mm |
| Stack | 544mm | 541 | −3 mm |
| Head tube angle | 73° | 73.0° | ±0.0° |
| Seat tube angle | 74° | not listed | |
| Effective top tube | 540mm | 543 | +3 mm |
| Chainstay length | 410mm | 410 | ±0 mm |
| Wheelbase | 978mm | 981 | +3 mm |
| BB drop | 72mm | 70 | −2 mm |
| BB height | 268mm | not listed | |
| Standover | 748mm | 744 | −4 mm |
| Seat tube length | 481mm | 496 | +15 mm |
| Fork length | 369mm | not listed | |
| Head tube length | 137mm | 131 | −6 mm |
Differences are the Trek Émonda ALR minus the Specialized Aethos Pro Shimano. Full charts: 2025 Specialized Aethos Pro Shimano, 2025 Trek Émonda ALR.
Where each sits in its class
Specialized Aethos Pro ShimanoTrek Émonda ALR
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 | Specialized Aethos Pro ShimanoPro - Shimano Ultegra Di2 | Trek Émonda ALRALR 5 |
|---|---|---|
| Frame | Specialized Aethos FACT | not listed |
| Shifter | Shimano Ultegra R8170 Di2 | not listed |
| Derailleur | Shimano Ultegra R8150 Di2 | not listed |
| Cassette | Shimano Ultegra | not listed |
| Chain | Shimano XT M8100 | not listed |
| Crankset | Shimano Ultegra R8100 | not listed |
| Wheelset | Roval Alpinist CL II | Bontrager Paradigm SL |
| Tire | Specialized S-Works Turbo 2BR | Bontrager R1 Hard-Case Lite |
| Brake | Shimano Ultegra R8170 | not listed |
| Seatpost | Roval Alpinist | not listed |
| Saddle | Specialized Power Pro | not listed |
| Fork | not listed | Trek Émonda ALR |
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