Quiver

2025 Trek Émonda ALR Disc Frameset vs 2025 Specialized Aethos Pro

The 52 is the Specialized Aethos Pro size closest to your 50 Trek Émonda ALR Disc Frameset. 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 Disc Frameset 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 Disc Frameset numbers we have for size 50 are missing the seat angle. The numbers below still compare.

Geometry side by side

MeasurementTrek Émonda ALR Disc Frameset 50Specialized Aethos Pro 52Difference
Reach378380mm+2 mm
Stack521527mm+6 mm
Head tube angle72.1°72.5°+0.4°
Effective top tube521531mm+10 mm
Chainstay length410410mm±0 mm
Wheelbase974975mm+1 mm
BB drop7274mm+2 mm
Standover711728mm+17 mm
Seat tube length453462mm+9 mm
Head tube length111120mm+9 mm
Seat tube anglenot listed74°
BB heightnot listed266mm
Fork lengthnot listed369mm

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

Where each sits in its class

Trek Émonda ALR Disc FramesetSpecialized 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.

What each ships with

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

PartTrek Émonda ALR Disc FramesetALR Disc FramesetSpecialized Aethos Pro
ForkTrek Émonda ALRnot listed

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