Abstract: A reciprocating piston machine, shown as having a crankshaft with a crank-pin offset from the axis of rotation of the crankshaft and a connecting rod pivotally connected at the end thereof remote from the crank-pin to a piston reciprocatingly received within a cylinder, has first and second eccentric bearings journalled with respect to each other and operatively collectively carried by the crank-pin and situated as to be generally between the crank-pin and the cooperating end of the related connecting rod; one of the eccentric bearings is rotated generally with the crank-pin and completely within the cooperating end of the connecting rod by the crankshaft during each full rotation of the crankshaft while the crank-pin undergoes one full rotation with respect to the other of the eccentric bearings for each full rotation of the crankshaft.