You and me both, lean540! I'd rather have experience than smarts. I followed the importer's notes for my Moki 2.10 and ran 3/32" fuel line throughout with no problem getting a rich enough mixture to load up the engine. I ran Morgan Mach7 5% fuel with 1/2 castor and 1/2 synthetic oil. I sold the engine to an ofb who changed fuels and added castor to whatever fuel he decided to run, and the fuel line would not flow enough to allow the mixture to richen up. Evidently the big Moki sucks enough fuel to make fuel line diameter critical and dependent on oil per centage. He replaced everything from the clunk to the carburetor with large diameter line in order to run his fuel. Also, don't even try to flip a big Moki through. For the first start of the day, make sure the engine is wet with fuel and merely bump the prop backwards; it will kick and start frontwards every time. All starts after that, don't even choke or prime, just bump backwards (or twist the spinner backwards!) and off you go. Terrific engine! My choice for any airplane up to thirty pounds...JIM