Quiver

2026 Specialized Aethos 2 vs 2025 Basso SV Shimano Dura Ace

The 48 is the Basso SV Shimano Dura Ace size closest to your 49 Specialized Aethos 2. 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 Basso SV Shimano Dura Ace

Compared with the Specialized Aethos 2 in 49, the Basso SV Shimano Dura Ace in 48 places the top of the head tube at about the same height and about as far forward, relative to the bottom bracket. Its wheelbase is 4 mm shorter, which can contribute to quicker direction changes.

Frame stack
−1 mm
About the same height
Frame reach
+2 mm
About the same reach
Wheelbase
−4 mm
Shorter: quicker to change direction
Head angle
+0.1°
About the same head angle
Chainstays
n/a
One of the bikes has no number for this

The two frames

2026 Specialized Aethos 2 (49)The Specialized Aethos 2 frame drawn to scale.J 978

Only the Specialized Aethos 2 is drawn. The Basso SV Shimano Dura Ace numbers we have for size 48 are missing the chainstay length.

Geometry side by side

MeasurementSpecialized Aethos 2 49Basso SV Shimano Dura Ace 48Difference
Reach373375+2 mm
Stack522521−1 mm
Head tube angle71.471.5+0.1°
Seat tube angle75.575−0.5°
Effective top tube508515+7 mm
Chainstay length410not listed
Wheelbase978974−4 mm
BB drop75.5not listed
Head tube length114115+1 mm
Standovernot listed744
Seat tube lengthnot listed455

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

Know what is on every bike.

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