Cannondale Synapse Carbon 3 SmartSense vs Specialized Roubaix SL8 Expert - 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 Specialized Roubaix SL8 Expert - Shimano Ultegra Di2 comes out ahead (76% against 68%). That is not a universal verdict — change the terrain or the priority and the order can flip.
What actually separates them
- Price
- The Cannondale Synapse Carbon 3 SmartSense is £254 cheaper — £4,995 against £5,249.
- Weight
- The Specialized Roubaix SL8 Expert - Shimano Ultegra Di2 is 1.7kg lighter, which you notice on long climbs more than anywhere else.
- Riding position
- The Specialized Roubaix SL8 Expert - Shimano Ultegra Di2 sits you more upright (1.56 stack-to-reach against 1.52). The Cannondale Synapse Carbon 3 SmartSense is the more aggressive of the two — quicker if you can hold it, harder work if you cannot.
- Tyre clearance
- The Cannondale Synapse Carbon 3 SmartSense takes 42mm tyres against 40mm — the single most common thing buyers wish they had more of.
- Climbing gear
- The Cannondale Synapse Carbon 3 SmartSense has the easier bottom gear (25 gear inches against 27), which matters more than weight on anything genuinely steep.
Side by side
| Spec | Synapse Carbon 3 SmartSense | Roubaix SL8 Expert - Shimano Ultegra Di2 |
|---|---|---|
| Price | £4,995 | £5,249 |
| Weight | 9.9 kg | 8.2 kg |
| Frame | carbon | carbon |
| Groupset | SRAM Rival AXS | Shimano Ultegra Di2 R8170 2x12 electronic |
| Stack / reach | 1.52 | 1.56 |
| Tyre clearance | 42 mm | 40 mm |
| Lowest gear | 25 in | 27 in |
| Mudguard mounts | Yes | Yes |
| Comfort | 68 | 73 |
| Speed | 36 | 53 |
| Climbing | 53 | 71 |
| 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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