Geometry ?
Chapter2 Rira 2026 geometry in sizes XS–XL: stack 489–601 mm, reach 361–401 mm, head angle 70–74°.
| XS | S | M | L | XL | |
|---|---|---|---|---|---|
| Stack | 489 mm | 517 mm | 545 mm | 573 mm | 601 mm |
| Reach | 361 mm | 371 mm | 381 mm | 391 mm | 401 mm |
| Head angle | 70° | 72° | 73° | 74° | 74° |
| Seat angle | 74° | 74° | 74° | 74° | 74° |
| Seat tube (?) | 430 mm | 450 mm | 470 mm | 500 mm | 530 mm |
| Head tube | 90 mm | 112 mm | 135 mm | 161 mm | 191 mm |
| Top tube (effective) | 502 mm | 520 mm | 538 mm | 555 mm | 574 mm |
| BB drop | 74 mm | 73.5 mm | 73 mm | 72.5 mm | 72 mm |
| Chainstay | 410 mm | 410 mm | 410 mm | 410 mm | 410 mm |
| Wheelbase | 972 mm | 974 mm | 975 mm | 982 mm | 1001 mm |
| Standover | 721 mm | 744 mm | 768 mm | 799 mm | 827 mm |
| Fork offset | 53 mm | 53 mm | 43 mm | 43 mm | 43 mm |
(?) by the seat tube length: the manufacturer doesn’t say whether it’s measured centre to centre (c-c) or centre to top (c-t).
Source: eu-de.chapter2bikes.com, checked 12 Nov 2026 · bar position: worked out from published data
Stock build
I don’t have the build for each size yet.
Frames with similar geometry
Stack and reach within 12 mm of size XS (stack 489 / reach 361 mm).
Stack and reach within 12 mm of size S (stack 517 / reach 371 mm).
Stack and reach within 12 mm of size M (stack 545 / reach 381 mm).
Stack and reach within 12 mm of size L (stack 573 / reach 391 mm).
Stack and reach within 12 mm of size XL (stack 601 / reach 401 mm).
Spotted a mistake or a missing build? Let me know.
Are you the manufacturer, or do you sell this bike? I’m missing 7 values for this model’s stem and bars. Add them