Quiver

2027 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 56 places the top of the head tube 19 mm higher and 11 mm further forward, relative to the bottom bracket. Its wheelbase is 10 mm longer, which can contribute to stability at speed.

Frame stack
+19 mm
Higher front end
Frame reach
+11 mm
Longer frame reach
Wheelbase
+10 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 56Difference
Reach384395mm+11 mm
Stack546565mm+19 mm
Head tube angle72.9°73.5°+0.6°
Effective top tube545562mm+17 mm
Chainstay length410410mm±0 mm
Wheelbase981991mm+10 mm
BB drop7072mm+2 mm
Standover762769mm+7 mm
Seat tube length476504mm+28 mm
Head tube length136157mm+21 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: 2027 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
FrameTrek Madonenot listed
ForkTrek Madone Gen 8not listed
ShifterSRAM Forcenot listed
DerailleurSRAM Force AXSnot listed
CassetteSRAM Force XG-1270not listed
ChainSRAM E1 Forcenot listed
CranksetSRAM Force AXSnot listed
Bottom bracketSRAM DUBnot listed
BatterySRAM eTapnot listed
WheelsetBontrager Aeolus Pro 51not listed
TireBontrager Aeolus RSL RDnot listed
BrakeSRAM Force AXSnot listed
RotorSRAM Pacelinenot listed
HandlebarTrek Aero RSL Roadnot listed
HeadsetBontrager Expander Plugnot listed
SeatpostTrek Madone aeronot listed
SaddleBontrager Aeolus Pronot listed

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