A rotor asks two things of a bike: a hub interface (Center Lock or 6-bolt) and a mount rated for its diameter. Both are safety-critical, so a rotor reads "fits" only when both are verified by two independent sources; with a single source the honest answer is "unknown", and with none it is "unknown — safety-critical".
- 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.