An agricultural harvester has a chassis carrying a threshing and separating system for separating grain from Material Other than Grain (MOG). The threshing and separating system has a threshing rotor and at least one concave. At least one rasp bar is attached to the threshing rotor. The at least one rasp bar has an upper threshing surface and a trailing surface. The trailing surface is set at a draft angle. At least one trailing surface interrupter is located on the trailing surface and may be inclined slightly rearward from vertical. The trailing surface interrupters may be used with rasp bars with or without rasp bar spikes.
