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Cannondale Synapse Carbon 3 L vs Specialized Roubaix SL8 Sport 105

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

The short answer

For a typical all-round rider the Cannondale Synapse Carbon 3 L comes out ahead (77% against 74%). That is not a universal verdict — change the terrain or the priority and the order can flip.

Cannondale

Synapse Carbon 3 L

77% for a typical rider

Unverified

Specialized

Roubaix SL8 Sport 105

74% for a typical rider

£2,800 at Sigma Sports

£100 under RRP. 30-day returns

Unverified

What actually separates them

Price
The Cannondale Synapse Carbon 3 L is £200 cheaper — £2,700 against £2,900.
Weight
The Specialized Roubaix SL8 Sport 105 is 0.2kg lighter, which you notice on long climbs more than anywhere else.
Riding position
The Cannondale Synapse Carbon 3 L sits you more upright (1.60 stack-to-reach against 1.56). The Specialized Roubaix SL8 Sport 105 is the more aggressive of the two — quicker if you can hold it, harder work if you cannot.
Tyre clearance
The Specialized Roubaix SL8 Sport 105 takes 40mm tyres against 35mm — the single most common thing buyers wish they had more of.
Shifting
Only the Cannondale Synapse Carbon 3 L has electronic shifting. Crisper and lower maintenance, but it needs charging and costs more to replace.
Mudguards
Only the Cannondale Synapse Carbon 3 L takes mudguards, which decides whether it can be your winter bike.

Side by side

Spec Synapse Carbon 3 L Roubaix SL8 Sport 105
Price £2,700 £2,900
Weight 9.1 kg 8.9 kg
Frame carbon carbon
Groupset Shimano 105 R7100 Di2 Shimano 105 R7100 mechanical
Stack / reach 1.60 1.56
Tyre clearance 35 mm 40 mm
Lowest gear 26 in 26 in
Mudguard mounts Yes No
Comfort 82 74
Speed 36 43
Climbing 62 65
Value 40 18

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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