Specialized Roubaix SL8 vs Specialized Tarmac SL9: geometry and fit comparison
Matched sizes, stack and reach deltas, and a fit check against your own body instead of guessing from two separate size charts.
The Specialized Roubaix SL8 is built as a endurance geometry frame, the Specialized Tarmac SL9 as a race geometry frame. The Specialized Tarmac SL9 cockpit runs about 21 mm longer, a noticeably more stretched position. Across matched sizes the Specialized Roubaix SL8 and Specialized Tarmac SL9 front ends are within a few millimetres of each other, so posture will depend more on cockpit setup than on the frame.
For the Specialized Roubaix SL8 in 61, 64 there is no Specialized Tarmac SL9 size with a comparable position: the range simply does not reach there.
Switching from a Specialized Roubaix SL8?
Your closest Specialized Tarmac SL9 size, and what will still feel different about the position.
| You ride the Specialized Roubaix SL8 in | Take the Specialized Tarmac SL9 in | The position will feel |
|---|---|---|
| 44 | 54 | 1 mm taller · 31 mm longerDifferent position |
| 49 | 54 | 5 mm lower · 21 mm longerDifferent position |
| 52 | 56 | 1 mm lower · 25 mm longerDifferent position |
| 54 | 58 | 6 mm taller · 21 mm longerDifferent position |
| 56 | 61 | 7 mm taller · 19 mm longerDifferent position |
| 58 | 61 | 18 mm lower · 11 mm longerDifferent position |
Which one fits you better?
Run the same measurements through both frames. The likely size and the full fit report can differ more than the spec sheets suggest.
What Specialized Roubaix SL8 size fits you?
Get an instant frame estimate, then continue into the full fit report to check cockpit reach, bar drop, and setup risks before you buy.
No account needed for this check. The full report keeps this bike preselected.
What Specialized Tarmac SL9 size fits you?
Get an instant frame estimate, then continue into the full fit report to check cockpit reach, bar drop, and setup risks before you buy.
No account needed for this check. The full report keeps this bike preselected.
FAQ
Which has the taller front end: Specialized Roubaix SL8 or Specialized Tarmac SL9?
Across matched sizes the Specialized Roubaix SL8 and Specialized Tarmac SL9 front ends are within a few millimetres of each other, so posture will depend more on cockpit setup than on the frame.
Can the same rider take different sizes on these two bikes?
Yes, and it happens often: frame labels are not standardized. Use the matched-size table for geometry, then run the fit check below with your own measurements for each bike.
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