Quiver

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

2025 Specialized Aethos Pro Shimano (54)The Specialized Aethos Pro Shimano frame drawn to scale.J 978

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

MeasurementSpecialized Aethos Pro Shimano 54Trek Émonda ALR 54Difference
Reach384mm386+2 mm
Stack544mm541−3 mm
Head tube angle73°73.0°±0.0°
Seat tube angle74°not listed
Effective top tube540mm543+3 mm
Chainstay length410mm410±0 mm
Wheelbase978mm981+3 mm
BB drop72mm70−2 mm
BB height268mmnot listed
Standover748mm744−4 mm
Seat tube length481mm496+15 mm
Fork length369mmnot listed
Head tube length137mm131−6 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

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 Pro ShimanoPro - Shimano Ultegra Di2Trek Émonda ALRALR 5
FrameSpecialized Aethos FACTnot listed
ShifterShimano Ultegra R8170 Di2not listed
DerailleurShimano Ultegra R8150 Di2not listed
CassetteShimano Ultegranot listed
ChainShimano XT M8100not listed
CranksetShimano Ultegra R8100not listed
WheelsetRoval Alpinist CL IIBontrager Paradigm SL
TireSpecialized S-Works Turbo 2BRBontrager R1 Hard-Case Lite
BrakeShimano Ultegra R8170not listed
SeatpostRoval Alpinistnot listed
SaddleSpecialized Power Pronot listed
Forknot listedTrek Émonda ALR

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