I must say that I have been very fortunate with running my engines inverted. I have run 2C and 4C inverted without any problems but for the first start of the day. Even that is sorted out by using an electric starter. What I have found to be helpful is a refueling valve, this ensures that the fuel does not over flow the carb when you are filling up. Taking some time to patiently tune the engine helps a lot. Guess, for me its listening to the manner in which the engine runs and throttles up.

One thing I hate is when we are not using a remote glow ... hate trying to fiddle to get the glow in!