With my OS 40LA (control line set-up), I found that it wanted to start very wet. In fact, I had to go out about 4 turns to get it to start. Also, I found that it runs much better with a Fox RC Long plug w/idle bar. I think, and this is only my theory, that the longer plug puts the element up above any fuel that would pool in the combustion chamber and flood it out. I don't know if this is right, but the long plug just seems to work better. My RC planes are have straight-up engines, so I can't say for sure if these techniques apply to RC, but I would think that, in general, they would.
Glen