Quiver

2027 Trek Madone SL Gen 8 First Replica 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 SL Gen 8 First Replica in M, the Specialized Aethos Pro in 52 places the top of the head tube 19 mm lower and 4 mm further back, relative to the bottom bracket. Its wheelbase is 6 mm shorter, which can contribute to quicker direction changes.

Frame stack
−19 mm
Lower front end
Frame reach
−4 mm
Shorter frame reach
Wheelbase
−6 mm
Shorter: quicker to change direction
Head angle
−0.4°
Slacker: calmer steering
Chainstays
±0 mm
About the same

The two frames

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

Geometry side by side

MeasurementTrek Madone SL Gen 8 First Replica MSpecialized Aethos Pro 52Difference
Reach384380mm−4 mm
Stack546527mm−19 mm
Head tube angle72.9°72.5°−0.4°
Effective top tube545531mm−14 mm
Chainstay length410410mm±0 mm
Wheelbase981975mm−6 mm
BB drop7074mm+4 mm
Standover762728mm−34 mm
Seat tube length476462mm−14 mm
Head tube length136120mm−16 mm
Seat tube anglenot listed74°
BB heightnot listed266mm
Fork lengthnot listed369mm

Differences are the Specialized Aethos Pro minus the Trek Madone SL Gen 8 First Replica. Full charts: 2027 Trek Madone SL Gen 8 First Replica, 2025 Specialized Aethos Pro.

Where each sits in its class

Trek Madone SL Gen 8 First ReplicaSpecialized 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 SL Gen 8 First ReplicaSL 7 Gen 8 - The First 50 ReplicaSpecialized Aethos Pro
ForkTrek Madone Gen 8not listed
ShifterShimano Ultegra R8170 Di2not listed
DerailleurShimano Ultegra R8150 Di2not listed
CassetteShimano Ultegra R8101not listed
ChainShimano XT M8100 Ultegra/XTnot listed
CranksetShimano Ultegra R8100not listed
WheelsetBontrager Aeolus Pro 51not listed
TireBontrager Aeolus Pronot listed
BrakeShimano Ultegranot listed
RotorShimano CL800not listed
StemTrek RCSnot listed
SeatpostTrek Madonenot listed
SaddleBontrager Aeolus Elitenot listed

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