A harvester reciprocating drive balancing system (20) may include a crop material separating member (30) movably supported for reciprocal movement (34) and a drive (32) operably coupled to the crop material separating member (30) to reciprocate the crop material separating member (30). The drive (32) may include a drive crank (40) operably coupled to the crop material separating member (30), a shaft (42) operably coupled to the drive crank (40), a belt drive (44), a driven pulley (46), a belt (48) wrapped about the belt drive (44) and the driven pulley (46) and a gear reduction mechanism (50) operably coupled between the driven pulley (46) and the shaft (42).