Polygon Siskiu T8 vs Specialized Epic 9: 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 Polygon Siskiu T8 is built as a cross-country geometry frame, the Specialized Epic 9 as a cross-country geometry frame. Across matched sizes the Polygon Siskiu T8 and Specialized Epic 9 front ends are within a few millimetres of each other, so posture will depend more on cockpit setup than on the frame. Reach is nearly identical across matched sizes.
Switching from a Polygon Siskiu T8?
Your closest Specialized Epic 9 size, and what will still feel different about the position.
| You ride the Polygon Siskiu T8 in | Take the Specialized Epic 9 in | The position will feel |
|---|---|---|
| S | M | 10 mm longer |
| M | M | 5 mm lower · 15 mm shorter |
| L | L | 4 mm lower · 5 mm shorter |
| XL | XL | 9 mm taller |
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 Polygon Siskiu T8 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 Epic 9 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: Polygon Siskiu T8 or Specialized Epic 9?
Across matched sizes the Polygon Siskiu T8 and Specialized Epic 9 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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