Quiver

2025 Specialized Aethos Pro vs 2025 Trek Émonda ALR

The 56 is the Trek Émonda ALR size closest to your 56 Specialized Aethos Pro. 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 in 56, the Trek Émonda ALR in 56 places the top of the head tube at about the same height and 4 mm further back, relative to the bottom bracket. Its wheelbase is 8 mm shorter, which can contribute to quicker direction changes.

Frame stack
−2 mm
About the same height
Frame reach
−4 mm
Shorter frame reach
Wheelbase
−8 mm
Shorter: quicker to change direction
Head angle
±0.0°
About the same head angle
Chainstays
±0 mm
About the same

The two frames

2025 Specialized Aethos Pro (56)The Specialized Aethos Pro frame drawn to scale.J 991

Only the Specialized Aethos Pro is drawn. The Trek Émonda ALR numbers we have for size 56 are missing the seat angle.

Geometry side by side

MeasurementSpecialized Aethos Pro 56Trek Émonda ALR 56Difference
Reach395mm391−4 mm
Stack565mm563−2 mm
Head tube angle73.5°73.5°±0.0°
Seat tube angle73.5°not listed
Effective top tube562mm559−3 mm
Chainstay length410mm410±0 mm
Wheelbase991mm983−8 mm
BB drop72mm70−2 mm
BB height268mmnot listed
Standover769mm768−1 mm
Seat tube length504mm525+21 mm
Fork length369mmnot listed
Head tube length157mm151−6 mm

Differences are the Trek Émonda ALR minus the Specialized Aethos Pro. Full charts: 2025 Specialized Aethos Pro, 2025 Trek Émonda ALR.

Where each sits in its class

Specialized Aethos ProTrek Émonda ALR

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.

What each ships with

The stock build of each bike's first listed trim. Parts that match are dimmed.

PartSpecialized Aethos ProTrek Émonda ALRALR 5
Forknot listedTrek Émonda ALR
Wheelsetnot listedBontrager Paradigm SL
Tirenot listedBontrager R1 Hard-Case Lite

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