An agricultural harvesting machine including a flexible cutterbar (22) and associated draper belts (32) for carrying cut agricultural material to a center location. The belts are guided by a drive rollers (70) and idler rollers. The idler roller for each belt is pivotable about an axis generally at 90 degrees to the axis of the belt and the drive roller for each belt is translatable axially to minimize diagonal stresses caused by flexing of the elongated endless belt.
