A machine having pairs of powered rollers for propelling ears of corn along a course through a cutter head assembly for kernel separation. A hydraulic motor drives each roller by means of a powered shaft which, along with the motor, may be displaced during roller contact with a passing ear of corn by reason of flexible motor mounts each inducing a yieldable distal portion for motor attachment. The motors are shown in fluid communication with a single source of pressurized fluid. Equalizer arms each associated with a powered shaft ensures uniform, opposite displacment of each pair of rollers during contact with an ear of corn. A link coupling each pair of equalizer arms, and indirectly the shafts associated therewith, effects uniform roller displacement to permit ear travel along an axial course through the machine.