A mobile baling machine (10) including a rotary input shaft (27) connected by way of a driveline to a rotatable flywheel (28)； and a drive converter (31) that converts rotation of the flywheel (28) to reciprocal rectilinear motion of a plunger (23) in a bale-forming chamber (22) forming part of the baling machine (10), in manner forming plant matter in the bale-forming chamber (22) into a compressed form； the driveline including one or more clutches (49, 54) for controlledly transferring rotary drive between the input shaft (27) and the flywheel (28), wherein the driveline includes a transmission (38) including driveline components defining at least first and second selectable transmission ratios (G1, G2) between the input shaft (27) and the flywheel (28)； and wherein the baling machine (10) includes or is operatively connected to one or more controllers (44) that selectively engage a relatively lower, first said transmission ratio (G1) or a relatively higher, second said transmission ratio (G2) in dependence on conditions prevailing in the baling machine (10).
