OS 61RF motor

OS rear exhaust 60 motor RF was disassembled thoroughly and the crankshaft supporting main bearings were replaced into new ones, R6Z for front and 6903 for rear promptly. Clogged and rusted piston pin prevented me from removing the connective rod from the crank pin, because some smooth axial movement between connective rod small end and piston pin was lost, rust was the criminal. Chronic slipping result was observed on the crankshaft as shinny mark on the rear bearing inner surface portion, the damage was not so critical, so it's reusable was my decision.
This OS 61 RF motor has not experienced breaking in and running in procedure, shinny spot on the piston vertical surface was removed with my best concentration and care. Because the carburetor fitted on was for the use under fuel mechanical pressure condition 86 butterfly throttle type, it was replaced into 7D carburetor with 8 mm diameter throat venturi. I prefer natural aspiration conditioned combustion to any fuel pressured circumstance caused by mechanical diaphragm pump, but YS regulator system is the only exception. According to my past experiences over 30 years ago, the diaphragm cannot follow the pulsing signal over 12,000 rpm, no matter how any diaphragm thin material might be invited, this phenomenon was observed even on an original Perry pomp system, so a diaphragm pump system should be used only the operation condition just under 8,000 rpm which means that suitable for four cycle motor?