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2027 Specialized Aethos 2 SRAM vs 2025 Basso SV Shimano Dura Ace

The Basso SV Shimano Dura Ace size closest to your 54 is the 53. Compare the 53 instead

What changes on the Basso SV Shimano Dura Ace

Compared with the Specialized Aethos 2 SRAM in 54, the Basso SV Shimano Dura Ace in 51 places the top of the head tube 12 mm lower and 4 mm further back, relative to the bottom bracket. Its wheelbase is 10 mm shorter, which can contribute to quicker direction changes.

Frame stack
−12 mm
Lower front end
Frame reach
−4 mm
Shorter frame reach
Wheelbase
−10 mm
Shorter: quicker to change direction
Head angle
−0.5°
Slacker: calmer steering
Chainstays
n/a
One of the bikes has no number for this

The two frames

2027 Specialized Aethos 2 SRAM (54)The Specialized Aethos 2 SRAM frame drawn to scale.J 992

Only the Specialized Aethos 2 SRAM is drawn. The Basso SV Shimano Dura Ace numbers we have for size 51 are missing the chainstay length.

Geometry side by side

MeasurementSpecialized Aethos 2 SRAM 54Basso SV Shimano Dura Ace 51Difference
Reach384mm380−4 mm
Stack559mm547−12 mm
Head tube angle72.5°72−0.5°
Seat tube angle74°74.7+0.7°
Effective top tube544mm530−14 mm
Chainstay length410mmnot listed
Wheelbase992mm982−10 mm
BB drop75mmnot listed
BB height267mmnot listed
Standover759mm772+13 mm
Seat tube length490mm485−5 mm
Fork length372mmnot listed
Head tube length150mm140−10 mm

Differences are the Basso SV Shimano Dura Ace minus the Specialized Aethos 2 SRAM. Full charts: 2027 Specialized Aethos 2 SRAM, 2025 Basso SV Shimano Dura Ace.

Where each sits in its class

Specialized Aethos 2 SRAMBasso SV Shimano Dura Ace

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 Aethos 2 SRAMS-Works - SRAM RED AXSBasso SV Shimano Dura AceShimano Dura Ace Di2
FrameSpecialized S-Works Aethos 2 FACTBasso SV
ShifterSRAM RED AXS E1Shimano Dura-Ace R9270
DerailleurSRAM RED AXS E1Shimano Dura-Ace R9250
CassetteSRAM RED XG-1290 E1Shimano Dura-Ace R9200
ChainSRAM Red E1 flat-topShimano Dura-Ace
CranksetSRAM RED AXS E1Shimano Dura-Ace R9200
Bottom bracketSpecialized AlphaShimano Dura-Ace R9200
WheelsetRoval Rapide CLXDT Swiss ARC 1100
TireSpecialized Cotton TLRContinental Grand Prix 5000
BrakeSRAM Red E1Shimano Dura-Ace R9270
HandlebarRoval Alpinist Cockpit IIBasso Fuga Integrated
SeatpostRoval Alpinistnot listed
SaddleSpecialized S-Works PowerSelle Italia SLR Superflow
Chainringnot listedShimano 52, Shimano 36
Rotornot listedShimano Dura Ace Ice Rotor
Stemnot listedBasso Fuga Integrated

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