Quiver

2027 Trek Madone SLR Gen 8 vs 2025 Specialized Aethos Pro

The 61 is the Specialized Aethos Pro size closest to your XL Trek Madone SLR Gen 8. 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 Madone SLR Gen 8 in XL, the Specialized Aethos Pro in 61 places the top of the head tube at about the same height and 6 mm further forward, relative to the bottom bracket. Its wheelbase is 5 mm longer, which can contribute to stability at speed.

Frame stack
+2 mm
About the same height
Frame reach
+6 mm
Longer frame reach
Wheelbase
+5 mm
Longer: steadier at speed
Head angle
+0.1°
About the same head angle
Chainstays
−2 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 XL are missing the seat angle. The numbers below still compare.

Geometry side by side

MeasurementTrek Madone SLR Gen 8 XLSpecialized Aethos Pro 61Difference
Reach402408mm+6 mm
Stack610612mm+2 mm
Head tube angle73.9°74°+0.1°
Effective top tube584595mm+11 mm
Chainstay length412410mm−2 mm
Wheelbase10071012mm+5 mm
BB drop6872mm+4 mm
Standover863824mm−39 mm
Seat tube length609567mm−42 mm
Head tube length201204mm+3 mm
Seat tube anglenot listed73°
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

Know what is on every bike.

Add your bike to Quiver. Keep its parts, setup, and service history together, then share your build.

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