Abstract: A lubrication system for a rotary piston internal-combustion engine of the trochoid type, including a roller or needle bearing for the rotor on the eccentric, wherein internal engine oil seals may be eliminated. A narrow annular clearance is provided between the shaft and the pinion of the synchromesh gearing, into which a dosed quantity of fresh oil may be pumped through the adjoining side part. At that side of this annular clearance which opens towards the eccentric, a splash edge is provided which is surrounded by a collector groove arranged at the eccentric. A passage in the eccentric leads from a radially outermost part of the collector groove towards the center of the rotor bearing. The pressurizing oil flowing into the annular clearance forces the oil to leave this space whereupon it is splashed off the splash edge under the action of the centrifugal force of the rotating shaft, and transferred into the collector groove from where it is passed through the bore in the eccentric into the rotor bearing.