This disclosure relates to a tire, a rim and a combination thereof that yields improved stability characteristics when the tire is run flat. The combination of this invention yields a structure wherein the tire will operate normally under normal conditions of load and pressure and will operate with the load equally distributed on each sidewall of the tire during run flat operation. In this invention, the tire has an asymmetric sidewall construction resulting from the inclusion of rubber inserts in its sidewalls of different bulk and the rim has axially outward extending rim flange extensions which are angled in relation to the axis of rotation of the rim. The extensions are angled in opposite directions. The proper combination of these features compensates for the camber that the tire is subjected to when it is run flat.