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2023 Trek Émonda SLR vs 2025 Specialized Aethos Pro

The Specialized Aethos Pro size closest to your 54 is the 54. Compare the 54 instead

What changes on the Specialized Aethos Pro

Compared with the Trek Émonda SLR in 54, the Specialized Aethos Pro in 52 places the top of the head tube 14 mm lower and 6 mm further back, relative to the bottom bracket. Its wheelbase is 6 mm shorter, which can contribute to quicker direction changes.

Frame stack
−14 mm
Lower front end
Frame reach
−6 mm
Shorter frame reach
Wheelbase
−6 mm
Shorter: quicker to change direction
Head angle
−0.5°
Slacker: calmer steering
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

MeasurementTrek Émonda SLR 54Specialized Aethos Pro 52Difference
Reach386380mm−6 mm
Stack541527mm−14 mm
Head tube angle73.0°72.5°−0.5°
Effective top tube543531mm−12 mm
Chainstay length410410mm±0 mm
Wheelbase981975mm−6 mm
BB drop7074mm+4 mm
Standover744728mm−16 mm
Seat tube length496462mm−34 mm
Head tube length131120mm−11 mm
Seat tube anglenot listed74°
BB heightnot listed266mm
Fork lengthnot listed369mm

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

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.

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