Quiver

2026 Specialized Aethos 2 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 in 54, the Basso SV Shimano Dura Ace in 45 places the top of the head tube 39 mm lower and 14 mm further back, relative to the bottom bracket. Its wheelbase is 21 mm shorter, which can contribute to quicker direction changes.

Frame stack
−39 mm
Lower front end
Frame reach
−14 mm
Shorter frame reach
Wheelbase
−21 mm
Shorter: quicker to change direction
Head angle
−1.3°
Slacker: calmer steering
Chainstays
n/a
One of the bikes has no number for this

The two frames

2026 Specialized Aethos 2 (54)The Specialized Aethos 2 frame drawn to scale.J 992

Only the Specialized Aethos 2 is drawn. The Basso SV Shimano Dura Ace numbers we have for size 45 are missing the chainstay length.

Geometry side by side

MeasurementSpecialized Aethos 2 54Basso SV Shimano Dura Ace 45Difference
Reach384370−14 mm
Stack559520−39 mm
Head tube angle72.571.2−1.3°
Seat tube angle7475.5+1.5°
Effective top tube544505−39 mm
Chainstay length410not listed
Wheelbase992971−21 mm
BB drop75not listed
Head tube length150115−35 mm
Standovernot listed722
Seat tube lengthnot listed420

Differences are the Basso SV Shimano Dura Ace minus the Specialized Aethos 2. Full charts: 2026 Specialized Aethos 2, 2025 Basso SV Shimano Dura Ace.

Where each sits in its class

Specialized Aethos 2Basso 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 2S-WorksBasso SV Shimano Dura AceShimano Dura Ace Di2
FrameSpecialized Aethos 2Basso SV
ShifterSRAM REDShimano Dura-Ace R9270
DerailleurSRAM Red AXS E1Shimano Dura-Ace R9250
CassetteShimano Dura-Ace R9200Shimano Dura-Ace R9200
ChainSRAM RED E1Shimano Dura-Ace
CranksetSRAM Powermeter Red AXSShimano Dura-Ace R9200
ChainringShimano Dura-Ace R9200Shimano 52, Shimano 36
Bottom bracketSRAM DUBShimano Dura-Ace R9200
WheelsetRoval Alpinist CLX IIIDT Swiss ARC 1100
TireSpecialized Turbo TLR RaceContinental Grand Prix 5000
HubRoval LF21-Fnot listed
BrakeShimano Dura-Ace R9200Shimano Dura-Ace R9270
RotorShimano Dura-Ace R9200Shimano Dura Ace Ice Rotor
HandlebarRoval Alpinist Cockpit IIBasso Fuga Integrated
StemRoval Alpinist Cockpit IIBasso Fuga Integrated
Bar tapeSupacaz Super Sticky Kushnot listed
HeadsetCeramicSpeed SLTnot listed
SeatpostRoval Alpinistnot listed
SaddleSpecialized PowerSelle Italia SLR Superflow

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