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2026 Trek Madone SLR Gen 8 vs 2025 Specialized Aethos Pro

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

What changes on the Specialized Aethos Pro

Compared with the Trek Madone SLR Gen 8 in M, the Specialized Aethos Pro in 49 places the top of the head tube 32 mm lower and 9 mm further back, relative to the bottom bracket. Its wheelbase is 8 mm shorter, which can contribute to quicker direction changes.

Frame stack
−32 mm
Lower front end
Frame reach
−9 mm
Shorter frame reach
Wheelbase
−8 mm
Shorter: quicker to change direction
Head angle
−1.2°
Slacker: calmer steering
Chainstays
±0 mm
About the same

The two frames

We can't draw these frames yet. The Trek Madone SLR Gen 8 numbers we have for size M are missing the seat angle. The numbers below still compare.

Geometry side by side

MeasurementTrek Madone SLR Gen 8 MSpecialized Aethos Pro 49Difference
Reach384375mm−9 mm
Stack546514mm−32 mm
Head tube angle72.9°71.75°−1.2°
Effective top tube545508mm−37 mm
Chainstay length410410mm±0 mm
Wheelbase981973mm−8 mm
BB drop7074mm+4 mm
Standover762705mm−57 mm
Seat tube length476431mm−45 mm
Head tube length136109mm−27 mm
Seat tube anglenot listed75.5°
BB heightnot listed266mm
Fork lengthnot listed369mm

Differences are the Specialized Aethos Pro minus the Trek Madone SLR Gen 8. Full charts: 2026 Trek Madone SLR Gen 8, 2025 Specialized Aethos Pro.

Where each sits in its class

Trek Madone SLR Gen 8Specialized 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 Madone SLR Gen 8SLR 7 AXS Gen 8Specialized Aethos Pro
ForkTrek Madone Gen 8 one-piecenot listed
WheelsetBontrager Aeolus Pro 51not listed
TirePirelli P Zeronot listed
HandlebarTrek RSLnot listed

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