A harvesting machine includes a main frame having a main actuator; a cutting frame having a crop guiding surface including a plurality of slots extending in a direction of travel of crop over the crop guiding surface and a plurality of knives pivotally mounted below the crop guiding surface; an outer frame being pivotable around a common pivot axis and being connected to the actuator; an inner frame having a plurality of operating units, and a selector mechanism configured to selectively engage one or more of the plurality of operating units. The outer frame includes an axis for pivotally holding a plurality of levers, each lever being pivotally connected to an operating unit of each knife. Guides are provided for lateral movement of the crop guiding surface with the plurality of knives from an operating position into a servicing position and vice versa.