Quiver

2025 Specialized Aethos 2 Expert 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 Expert 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

2025 Specialized Aethos 2 Expert (54)The Specialized Aethos 2 Expert frame drawn to scale.J 992

Only the Specialized Aethos 2 Expert 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 Expert 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
BB height267not listed
Standover759722−37 mm
Seat tube length490420−70 mm
Head tube length150115−35 mm

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

Where each sits in its class

Specialized Aethos 2 ExpertBasso 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 ExpertExpertBasso 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
Bottom bracketSRAM DUB GXShimano Dura-Ace R9200
WheelsetRoval C38DT Swiss ARC 1100
TireS Works TurboContinental Grand Prix 5000
BrakeSRAM Force E1Shimano Dura-Ace R9270
RotorShimano Ultegra R8170Shimano Dura Ace Ice Rotor
HandlebarRoval AlpinistBasso Fuga Integrated
StemSpecialized Pro SLBasso Fuga Integrated
GripsSupacaz Super Sticky Kushnot listed
SeatpostRoval Alpinistnot listed
SaddleSpecialized Power ExpertSelle Italia SLR Superflow
Chainringnot listedShimano 52, Shimano 36

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