The adaptor bar enables the user of our AllRim Bead Breaker, or any earlier version of the ram-rod bead breaker, to operate the machine on the reverse side of a truck wheel rim, or if the hub face is not either level with the outer rim edge or proud of the rim edge. The bar bridges across the rear rim face and provides a strong and stable platform to enable operation of the bead breaker even where conventional mounting is compromised.