Quiver

2026 Specialized Aethos 2 Pro vs 2025 Basso SV Shimano Dura Ace

The 48 is the Basso SV Shimano Dura Ace size closest to your 49 Specialized Aethos 2 Pro. 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 Pro 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 Pro (49)The Specialized Aethos 2 Pro frame drawn to scale.J 978

Only the Specialized Aethos 2 Pro 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 Pro 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 Pro. Full charts: 2026 Specialized Aethos 2 Pro, 2025 Basso SV Shimano Dura Ace.

Where each sits in its class

Specialized Aethos 2 ProBasso 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 ProProBasso SV Shimano Dura AceShimano Dura Ace Di2
FrameSpecialized Aethos 2Basso SV
ShifterSRAM Force AXS E1Shimano Dura-Ace R9270
DerailleurSRAM Force AXS E1Shimano Dura-Ace R9250
CassetteSRAM ForceShimano Dura-Ace R9200
ChainSRAM Force D1Shimano Dura-Ace
CranksetSRAM Force E1 XPLR 1xShimano Dura-Ace R9200
ChainringSRAM Force E1Shimano 52, Shimano 36
Bottom bracketSRAM DUB GXShimano Dura-Ace R9200
WheelsetRoval Alpinist CL IIDT Swiss ARC 1100
TireSpecialized Turbo TLR RaceContinental Grand Prix 5000
BrakeSRAM Force E1Shimano Dura-Ace R9270
RotorSRAM Force E1Shimano Dura Ace Ice Rotor
HandlebarRoval Alpinist Cockpit IIBasso Fuga Integrated
StemRoval Alpinist Cockpit IIBasso Fuga Integrated
GripsSupacaz Super Sticky Kushnot listed
SeatpostRoval Alpinist Carbon S-Worksnot listed
SaddleSpecialized Power Pro MirrorSelle Italia SLR Superflow

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