2023 Trek Émonda SLR vs 2025 Specialized Aethos Pro
The 54 is the Specialized Aethos Pro size closest to your 54 Trek Émonda SLR. 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 Aethos Pro
Compared with the Trek Émonda SLR in 54, the Specialized Aethos Pro in 54 places the top of the head tube 3 mm higher and about as far forward, relative to the bottom bracket. Its wheelbase is 3 mm shorter, which can contribute to quicker direction changes.
- Frame stack
- +3 mm
- Higher front end
- Frame reach
- −2 mm
- About the same reach
- Wheelbase
- −3 mm
- Shorter: quicker to change direction
- Head angle
- ±0.0°
- About the same head angle
- Chainstays
- ±0 mm
- About the same
The two frames
We can't draw these frames yet. The Trek Émonda SLR numbers we have for size 54 are missing the seat angle. The numbers below still compare.
Geometry side by side
| Measurement | Trek Émonda SLR 54 | Specialized Aethos Pro 54 | Difference |
|---|---|---|---|
| Reach | 386 | 384mm | −2 mm |
| Stack | 541 | 544mm | +3 mm |
| Head tube angle | 73.0° | 73° | ±0.0° |
| Effective top tube | 543 | 540mm | −3 mm |
| Chainstay length | 410 | 410mm | ±0 mm |
| Wheelbase | 981 | 978mm | −3 mm |
| BB drop | 70 | 72mm | +2 mm |
| Standover | 744 | 748mm | +4 mm |
| Seat tube length | 496 | 481mm | −15 mm |
| Head tube length | 131 | 137mm | +6 mm |
| Seat tube angle | not listed | 74° | |
| BB height | not listed | 268mm | |
| Fork length | not listed | 369mm |
Differences are the Specialized Aethos Pro minus the Trek Émonda SLR. Full charts: 2023 Trek Émonda SLR, 2025 Specialized Aethos Pro.
Where each sits in its class
Trek Émonda SLRSpecialized Aethos Pro
Each bike is ranked against the other road bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.
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