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Cervélo Caledonia-5 Ultegra Di2 vs Specialized Aethos 2 Pro - Shimano Ultegra Di2

Both are endurance bikes at a similar price. Here is what actually separates them.

The short answer

For a typical all-round rider the Cervélo Caledonia-5 Ultegra Di2 comes out ahead (79% against 76%). That is not a universal verdict — change the terrain or the priority and the order can flip.

Cervélo

Caledonia-5 Ultegra Di2

79% for a typical rider

£7,000 at Brand website
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Specialized

Aethos 2 Pro - Shimano Ultegra Di2

76% for a typical rider

£7,249 at Brand website
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What actually separates them

Price
The Cervélo Caledonia-5 Ultegra Di2 is £249 cheaper — £7,000 against £7,249.
Weight
The Specialized Aethos 2 Pro - Shimano Ultegra Di2 is 0.7kg lighter, which you notice on long climbs more than anywhere else.
Tyre clearance
The Cervélo Caledonia-5 Ultegra Di2 takes 41mm tyres against 35mm — the single most common thing buyers wish they had more of.
Climbing gear
The Cervélo Caledonia-5 Ultegra Di2 has the easier bottom gear (29 gear inches against 32), which matters more than weight on anything genuinely steep.
Mudguards
Only the Cervélo Caledonia-5 Ultegra Di2 takes mudguards, which decides whether it can be your winter bike.

Side by side

Spec Caledonia-5 Ultegra Di2 Aethos 2 Pro - Shimano Ultegra Di2
Price £7,000 £7,249
Weight 7.4 kg 6.7 kg
Frame carbon carbon
Groupset Shimano Ultegra Di2 2x12 electronic Shimano Ultegra Di2 R8100 2x12 electronic
Stack / reach 1.50 1.48
Tyre clearance 41 mm 35 mm
Lowest gear 29 in 32 in
Mudguard mounts Yes No
Comfort 63 47
Speed 69 83
Climbing 78 77
Value 0 0

Neither might be the right answer

This page assumes an average rider. Tell us how you actually ride and we will rank these two against everything else at the price.

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