Sealing means for a pneumatic tire and wheel rim assembly in which the wheel rim has a pair of axially spaced bead seats defined by grooves in each of which a respective one of a pair of axially spaced tire beads is located and retained. The sealing means comprises two seal elements each having a resiliently deformable portion which acts between confronting axially directed surfaces of the associated tire bead and bead seat to facilitate assembly and subsequently hold the tire bead under compression in an axial direction to prevent the tire bead slipping relative to the wheel rim.