A tire assembly includes: a tire having a pneumatic cavity; first and second sidewalls extending respectively from first and second tire bead regions to a tire tread region, the first sidewall having at least one bending region operatively bending when circumferentially adjacent a rolling tire footprint; a sidewall groove defined by groove sidewalls positioned within the bending region of the first tire sidewall, the groove deforming segment by segment between a non-deformed state and a deformed, constricted state in response to the bending of the first sidewall bending region circumferentially adjacent the rolling tire footprint; an air passageway resiliently deforming segment by segment between an expanded condition and an at least partially collapsed condition in response to respective segment by segment deformation of the sidewall groove when circumferentially adjacent the rolling tire footprint; and an assembly mounted to the first sidewall the tire, the assembly including a pressure regulator with an elongate cylindrical housing and a rectangular mounting plate, the mounting plate having an inlet port and two outlet ports for controlling air flow from outside of the tire to and from the pneumatic cavity.