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
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
| Measurement | Specialized Aethos 2 SRAM 54 | Basso SV Shimano Dura Ace 51 | Difference |
|---|---|---|---|
| Reach | 384mm | 380 | −4 mm |
| Stack | 559mm | 547 | −12 mm |
| Head tube angle | 72.5° | 72 | −0.5° |
| Seat tube angle | 74° | 74.7 | +0.7° |
| Effective top tube | 544mm | 530 | −14 mm |
| Chainstay length | 410mm | not listed | |
| Wheelbase | 992mm | 982 | −10 mm |
| BB drop | 75mm | not listed | |
| BB height | 267mm | not listed | |
| Standover | 759mm | 772 | +13 mm |
| Seat tube length | 490mm | 485 | −5 mm |
| Fork length | 372mm | not listed | |
| Head tube length | 150mm | 140 | −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
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.
| Part | Specialized Aethos 2 SRAMS-Works - SRAM RED AXS | Basso SV Shimano Dura AceShimano Dura Ace Di2 |
|---|---|---|
| Frame | Specialized S-Works Aethos 2 FACT | Basso SV |
| Shifter | SRAM RED AXS E1 | Shimano Dura-Ace R9270 |
| Derailleur | SRAM RED AXS E1 | Shimano Dura-Ace R9250 |
| Cassette | SRAM RED XG-1290 E1 | Shimano Dura-Ace R9200 |
| Chain | SRAM Red E1 flat-top | Shimano Dura-Ace |
| Crankset | SRAM RED AXS E1 | Shimano Dura-Ace R9200 |
| Bottom bracket | Specialized Alpha | Shimano Dura-Ace R9200 |
| Wheelset | Roval Rapide CLX | DT Swiss ARC 1100 |
| Tire | Specialized Cotton TLR | Continental Grand Prix 5000 |
| Brake | SRAM Red E1 | Shimano Dura-Ace R9270 |
| Handlebar | Roval Alpinist Cockpit II | Basso Fuga Integrated |
| Seatpost | Roval Alpinist | not listed |
| Saddle | Specialized S-Works Power | Selle Italia SLR Superflow |
| Chainring | not listed | Shimano 52, Shimano 36 |
| Rotor | not listed | Shimano Dura Ace Ice Rotor |
| Stem | not listed | Basso Fuga Integrated |
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