Quiver

2025 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 58 places the top of the head tube 45 mm higher and 18 mm further forward, relative to the bottom bracket. Its wheelbase is 24 mm longer, which can contribute to stability at speed.

Frame stack
+45 mm
Higher front end
Frame reach
+18 mm
Longer frame reach
Wheelbase
+24 mm
Longer: steadier at speed
Head angle
+0.6°
Steeper: sharper 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 58Difference
Reach384402mm+18 mm
Stack546591mm+45 mm
Head tube angle72.973.5°+0.6°
Effective top tube545577mm+32 mm
Chainstay length410410mm±0 mm
Wheelbase9811005mm+24 mm
BB drop7072mm+2 mm
Standover762796mm+34 mm
Seat tube length476532mm+56 mm
Head tube length136184mm+48 mm
Seat tube anglenot listed73.5°
BB heightnot listed268mm
Fork lengthnot listed369mm

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