I would guess that 90% of the users just run them dry and forget about it. Disconnecting the engine completely from the tank is done prior to running the engine dry. If you can't do this, at least pinch the lines off where they enter the engine, then run it dry and leave it pinched until it's time to go flying again.
The only after run oil commercially available for the YS which is fully compatible with the fuel system is "Ultra-Oil", available from Performance Specialties at 775-265-7523.
Since the YS engines run the fuel charge through the crankcase, they tend to have less corrosion problems than other brands of four stroke.
The biggest deal is getting the engine run completely dry when you are finished for the day. Do that and the battle is largely won.

Dave