Hub spacing alone does not identify a replacement axle. The frame or fork must also agree with its thread pitch, length and head-seat geometry. An absent measurement is left unknown.
- How do I know whether a part in this category fits my bike?
- Every part page lists the standards it requires and its computed verdict on each bike in the fleet, with its confidence and sources. An "unknown" verdict means we do not have the measurement on file — not that it fits.