A groove is positioned within the bending region of the first tire sidewall and deforms segment by segment within the rolling tire footprint. An air tube positioned within the sidewall groove is in contacting engagement with groove sidewalls and resiliently squeezes and collapses segment by segment as the groove constricts segment by segment within the rolling tire footprint. A series of adjacent projecting ridges extend from a groove sidewall segment into the groove air passageway, the projecting ridges operatively positioned to vary the applied pressure on the air tube increase the air pressure within the air tube passageway as the air tube rolls segment by segment with the tire through tire footprint. The series of projecting ridges are constructed having a variable amplitude and/or spacing frequency in a direction of air flow within the air passageway to increase the pressure applied to the air tube and air pressure of the air flowing through the tube passageway.