Well... anything richer than 14-15:1 at cruise is wasting it... and with a 10 gal fuel cell the range is limited as it is.
With the previous carb (800 DP I converted to 4-corner idle and adjustable brass, new QFT baseplate and a lot of tuning) I was able to get 9.2 mpg on my last tank, almost all at a steady 60 mph cruise. Much less when standing on it, of course, but I can only do that for a few seconds at a time! :p
