Crust Bombora Frameset Geometry & Bikepacking Bag Fit2026
The same page we read this geometry from. We don't hold live pricing or stock for frames, so check both there.
We may earn a commission if you buy through this link, at no extra cost to you.
Crust Bombora Frameset frame geometry, drawn to scale
Every tube angle and length below is from the published chart, not an illustration. The front triangle area is the number that decides which frame bags fit — and it changes a lot across sizes.
What this frame gives a loaded bike
Chainstay length is the gap between the seat tube and the rear axle, which a rack, panniers and your heels all have to share. Bottom bracket drop is how far the cranks sit below the axles. Both are compared against the median across every current frame we hold.
425mm chainstays, 10mm shorter than the 435mm median across the 65 current frames here. Bottom bracket drop 64mm, 6mm less than the 70mm median. Crust publishes no fork cargo mounts, and no frame bottle positions are published. Crust states the frame does not take a rear rack. Widest published tire 58mm on 650b / 27.5in, 48mm on 700c / 29in.
Every figure above is the manufacturer's, computed against the rest of the database. It says what the frame allows, not how it feels — nobody here has ridden it.
What it can carry
Mount provision and clearance, as Crust publishes it.
Crust's wording: “Designed around a 650b/ 27.5" Wheel with a 2.3" max tire size. If you want to run it 700c, your max clearance will be a 48mm tire.”
Geometry
All figures in millimeters except angles. Effective top tube and seat tube are the two that decide frame bag fit.
| Size | Eff. top tube | Seat tube | Standover | Head tube | Stack | Reach | Chainstay | Wheelbase | BB drop | Head angle | Seat angle |
|---|---|---|---|---|---|---|---|---|---|---|---|
| XS | 520 | 456 | 747 | 121 | 540 | 365 | 425 | 1008 | 64 | 69.5° | 74.5° |
| Small | 540 | 502 | 775 | 132 | 553 | 378 | 425 | 1020 | 64 | 70° | 74° |
| Medium | 560 | 543 | 804 | 153 | 576 | 382 | 425 | 1023 | 64 | 71° | 73° |
| Large | 580 | 574 | 832 | 177 | 599 | 395 | 425 | 1043 | 64 | 71° | 73° |
| XL | 600 | 629 | 872 | 208 | 628 | 406 | 425 | 1064 | 64 | 71° | 73° |
| XXL | 620 | 670 | 907 | 241 | 660 | 416 | — | 1085 | 64 | 71° | 73° |
Bottom bracket height
Roughly 307mm off the ground. Crust doesn't publish this directly — we derive it from their BB drop and a typical 74.2cm tire diameter, so treat it as indicative rather than exact. It changes with the tire you fit. Lower means more stable and more pedal strikes; higher means the opposite.
Source — Crust's own geometry chart: https://crustbikes.com/collections/all/products/bombora — checked 2026-08-18. A dash means the figure isn't published; we leave it blank rather than estimate.
Note: Crust does not state a model year on the product page; modelYear is set to 2026 for the current manufacturer page. Geometry chart is metric millimeters. Current product size selector lists XS through XL, but the manufacturer's geometry chart also publishes XXL; XXL chainstay is blank in the chart and returned null. Sold as a frameset; priceFrom is the frameset price, not a complete bike.
Questions people ask about this frame
Answered from what Crust publish. Where they publish nothing, that is what it says.
Does the Bombora Frameset take fork cargo cages?
Not published. Crust don't state any fork mount provision for this frame. That isn't the same as it having none, and we won't guess from a photo.
What is the widest tyre the Bombora Frameset takes?
58mm on 650b / 27.5in. Across the wheel sizes Crust publish: 48mm on 700c / 29in, 58mm on 650b / 27.5in. Those are frame figures, not the fork's — forks are routinely cut for more rubber than the rear triangle.
Will a seat pack work on the Bombora Frameset?
Not published. Crust don't state dropper compatibility for this frame, so we can't tell you whether a dropper would compete with a seat pack on it.
Which frame bags fit
Every frame bag we track, checked against this frame's published geometry. Pick your size.
Checking 16 frame bags against a 580mm effective top tube and 574mm seat tube. 16 fit.
Frame bag fit is calculated from Crust's published geometry, so it's as reliable as their chart. Seat packs and handlebar rolls depend on your exposed seatpost and bar width, which no geometry table lists — the bag finder covers those once you add your own measurements.