BMC Kaius 2026 geometry

Size chart for fitting. If this bike already feels right, find others with a similar riding position (size 47). Category: gravel.
| Size | Stack | Reach | Head tube angle | Seat tube angle | Chainstay | Wheelbase | BB drop |
|---|---|---|---|---|---|---|---|
| 47 | 531 mm | 375 mm | 70.5° | 74.0° | 425 mm | 1011 mm | 76 mm |
| 51 | 551 mm | 383 mm | 71.0° | 73.7° | 425 mm | 1021 mm | 76 mm |
| 54 | 569 mm | 390 mm | 71.5° | 73.5° | 425 mm | 1031 mm | 74 mm |
| 56 | 587 mm | 397 mm | 71.5° | 73.2° | 425 mm | 1041 mm | 74 mm |
| 58 | 607 mm | 404 mm | 72.0° | 73.0° | 425 mm | 1053 mm | 72 mm |
| 61 | 627 mm | 411 mm | 72.0° | 73.0° | 425 mm | 1065 mm | 72 mm |
Similar bikes
Closest matches to this riding position — free, no login.
Trek Boone 2026Size 49 · 531 mm / 375 mm
Specialized Crux 2026Size 49 · 531 mm / 375 mm
Specialized S-Works Crux 2026Size 49 · 531 mm / 375 mm
Trek Boone 2025Size 49 · 530 mm / 375 mm
Trek Boone 2027Size 49 · 531 mm / 375 mm
Specialized Crux 2025Size 49 · 530 mm / 375 mm
Specialized Crux 2027Size 49 · 531 mm / 375 mm
BMC Kaius 2025Size 47 · 530 mm / 375 mm
Size guidance
Stack and reach describe the frame's cockpit envelope better than traditional seat-tube sizing. If you know your preferred stack/reach from a bike that already fits, search within a few millimeters first, then check head angle and chainstay for handling feel. See the glossary for stack, reach, and HTA.