A twin crankshaft piston engine with at least one piston cylinder unit, comprising: - a cylinder in which a reciprocating piston (1; 201; 301) is disposed, so that it can move back and forth; - a first crankshaft; - a second crankshaft; - wherein the first crankshaft and the second crankshaft extend parallel to one another and rotate synchronously in opposite directions; - wherein the rotation axes (Y1, Y2) of the two crankshafts (3, 4) extend parallel to a common cylinder center plane and are laterally offset with respect to the cylinder center plane; - wherein a first and a second connecting rod (5, 6) is associated with the reciprocating piston (1; 201; 301) in such a manner t hat the first connecting rod is pivotably supported with its first end at the reciprocating piston (1; 201; 301) in a first pivot bearing (55; 255; 355) about a first connecting rod pivot axis and rotatably supported with its second end at a crank pin of the first crankshaft and t hat the second connecting rod is pivotably supported with its first end at the reciprocating piston (1; 201; 301) in a second pivot bearing (65; 265; 365) about a second connecting rod pivot axis and rotatably supported with its second end at a crank pin of the second crankshaft, - wherein the pivot bearings (55, 65; 255, 265; 355, 365) are provided at a bearing element (12; 212; 312) which is pivotably supported at the piston (1; 201; 301) about a bearing element pivot axis which extends parallel to the connecting rod pivot axes (Y5, Y6) characterized - in that the assembly including the two crankshafts (3, 4) rotating synchronously in opposite directions is configured in such a manner that the crank pins (32, 42) rotate in opposite directions, but with a slight asymmetry, already in a new condition when no wear and tear occured. - a cylinder in which a reciprocating piston (1; 201; 301) is disposed, so that it can move back and forth; - a first crankshaft; - a second crankshaft; - wherein the first crankshaft and the second crankshaft extend parallel to one another and rotate synchronously in opposite directions; - wherein the rotation axes (Y1, Y2) of the two crankshafts (3, 4) extend parallel to a common cylinder center plane and are laterally offset with respect to the cylinder center plane; - wherein a first and a second connecting rod (5, 6) is associated with the reciprocating piston (1; 201; 301) in such a manner t hat the first connecting rod is pivotably supported with its first end at the reciprocating piston (1; 201; 301) in a first pivot bearing (55; 255; 355) about a first connecting rod pivot axis and rotatably supported with its second end at a crank pin of the first crankshaft and t hat the second connecting rod is pivotably supported with its first end at the reciprocating piston (1; 201; 301) in a second pivot bearing (65; 265; 365) about a second connecting rod pivot axis and rotatably supported with its second end at a crank pin of the second crankshaft, t hat the first connecting rod is pivotably supported with its first end at the reciprocating piston (1; 201; 301) in a first pivot bearing (55; 255; 355) about a first connecting rod pivot axis and rotatably supported with its second end at a crank pin of the first crankshaft and t hat the second connecting rod is pivotably supported with its first end at the reciprocating piston (1; 201; 301) in a second pivot bearing (65; 265; 365) about a second connecting rod pivot axis and rotatably supported with its second end at a crank pin of the second crankshaft, - wherein the pivot bearings (55, 65; 255, 265; 355, 365) are provided at a bearing element (12; 212; 312) which is pivotably supported at the piston (1; 201; 301) about a bearing element pivot axis which extends parallel to the connecting rod pivot axes (Y5, Y6) - in that the assembly including the two crankshafts (3, 4) rotating synchronously in opposite directions is configured in such a manner that the crank pins (32, 42) rotate in opposite directions, but with a slight asymmetry, already in a new condition when no wear and tear occured.