2025 Trek Émonda ALR vs 2025 Specialized Aethos Pro
The 52 is the Specialized Aethos Pro size closest to your 50 Trek Émonda ALR. 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 ALR in 50, the Specialized Aethos Pro in 52 places the top of the head tube 6 mm higher and about as far forward, relative to the bottom bracket.
- Frame stack
- +6 mm
- Higher front end
- Frame reach
- +2 mm
- About the same reach
- Wheelbase
- +1 mm
- About the same
- 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 Émonda ALR numbers we have for size 50 are missing the seat angle. The numbers below still compare.
Geometry side by side
| Measurement | Trek Émonda ALR 50 | Specialized Aethos Pro 52 | Difference |
|---|---|---|---|
| Reach | 378 | 380mm | +2 mm |
| Stack | 521 | 527mm | +6 mm |
| Head tube angle | 72.1° | 72.5° | +0.4° |
| Effective top tube | 521 | 531mm | +10 mm |
| Chainstay length | 410 | 410mm | ±0 mm |
| Wheelbase | 974 | 975mm | +1 mm |
| BB drop | 72 | 74mm | +2 mm |
| Standover | 711 | 728mm | +17 mm |
| Seat tube length | 453 | 462mm | +9 mm |
| Head tube length | 111 | 120mm | +9 mm |
| Seat tube angle | not listed | 74° | |
| BB height | not listed | 266mm | |
| Fork length | not listed | 369mm |
Differences are the Specialized Aethos Pro minus the Trek Émonda ALR. Full charts: 2025 Trek Émonda ALR, 2025 Specialized Aethos Pro.
Where each sits in its class
Trek Émonda ALRSpecialized Aethos 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 Émonda ALRALR 5 | Specialized Aethos Pro |
|---|---|---|
| Fork | Trek Émonda ALR | not listed |
| Wheelset | Bontrager Paradigm SL | not listed |
| Tire | Bontrager R1 Hard-Case Lite | not listed |
Know what is on every bike.
Add your bike to Quiver. Keep its parts, setup, and service history together, then share your build.
Explore the app
