valves and switching valves forms a hydraulic freewheel the running direction of which is selectable in the case of the position for a high compression ratio being selected also referred to as u201c u03b5_high u201d the mathematically positive moments acting on the eccentric are supported on the oil column of the gfs in this position the mathematically negatively acting moments arising from the inertia forces are transmitted by way of direct metallic contact of the ifs support piston to the connecting rod in the position of a low compression ratio referred to for short as u201c u03b5_low u201d the conditions are reversed a positive side effect for the position u201c u03b5_low u201d is that the normally relatively high gas forces in said position are now no longer supported on the oil column and thus the oil pressure in the support cylinder remains at a relatively low level the adjustment system of the support system of said type is thus equipped with a first and a second support piston wherein the two support pistons have different connections to the respective support rod one support piston 50 1 which has a ball head connection 54 has a smaller support piston diameter than the other support piston 50 2 which has a bolted connection 55 the lever transmits the moment arising from the eccentricity which moment may be greater than 300 nm owing to.