Quiver

2019 Specialized Tarmac SL6 vs 2021 Specialized Aethos

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

What changes on the Specialized Aethos

Compared with the Specialized Tarmac SL6 in 54, the Specialized Aethos in 58 places the top of the head tube 47 mm higher and 18 mm further forward, relative to the bottom bracket. Its wheelbase is 32 mm longer, which can contribute to stability at speed.

Frame stack
+47 mm
Higher front end
Frame reach
+18 mm
Longer frame reach
Wheelbase
+32 mm
Longer: steadier at speed
Head angle
+0.5°
Steeper: sharper steering
Chainstays
+5 mm
Longer: more planted

The two frames

2019 Specialized Tarmac SL6 (54) and 2021 Specialized Aethos (58), lined up at the bottom bracketBoth frames drawn to scale. The Specialized Tarmac SL6 is drawn in full with its measurements, and the Specialized Aethos is the colored outline on top.J 973

Specialized Tarmac SL6, 54Specialized Aethos, 58Drawn to scale and lined up at the bottom bracket.

Geometry side by side

MeasurementSpecialized Tarmac SL6 54Specialized Aethos 58Difference
Reach384402mm+18 mm
Stack544591mm+47 mm
Head tube angle7373.5°+0.5°
Seat tube angle7473.5°−0.5°
Effective top tube540not listed
Chainstay length405mm410mm+5 mm
Wheelbase973mm1005mm+32 mm
BB drop72mm72mm±0 mm
BB height268mm268mm±0 mm
Standover775796mm+21 mm
Seat tube length481532mm+51 mm
Fork length363mm369mm+6 mm
Head tube length143184mm+41 mm

Differences are the Specialized Aethos minus the Specialized Tarmac SL6. Full charts: 2019 Specialized Tarmac SL6, 2021 Specialized Aethos.

Where each sits in its class

Specialized Tarmac SL6Specialized Aethos

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.

PartSpecialized Tarmac SL6S-WorksSpecialized AethosAethos Frameset
FrameSpecialized S-Works Tarmac SL6Specialized Aethos FACT
Seatpostnot listedRoval Alpinist

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