This part of ISO 5775 specifies rim dimensions for bicycle tyres: it gives only those rim contour dimensions necessary for tyre mounting and to fit the tyre on the rim.

ISO 5775‑1 covers designations and dimensions for tyres.

ISO 5775‑2 covers straight side (SS) rims, hooked bead type (HB) rims and crotchet type (C) rims.