A bicycle wheel rim design with high safety margin and optimized strength-to-weight is described. The rim provides a tire bead supporting platform which defines a circumferential bead seat with minimum bead seat diameter equal to the standard tire bead diameter defined for a particular size of tire. Each tire bead seat defined along the rim circumference is comprised by a pair of circumferential ridges. The circumferential ridges comprise the external sidewalls of the rim and do not include tire bead hook features, and are of optimized sidewall thickness to add load strength and lateral stiffness, and resist crushing from impact. The interior ridges are increased diameter towards the medial plane of the rim to a value greater than the specified tire bead diameter. Given this geometry, the left lateral and right lateral of each tire bead is safely constrained within the defined bead seats under a wide variety of uses.