ORIGINAL: gaRCfield
Saito engines are known to come with a very rich idle mixture. They will run fine this way giving little to know indication (except short flight times) that the mixture should be leaned out. I have read about this a lot over the past couple of years on this forum. Just some food for thought.
Let me also confirm that!
I was flying my plane for a while but I never seemed to get a reliable idle...
I found the needle was over 11 turns OUT from ideal, even after leaning the engine!
And the engine still ran this way... wow.
The advice that I was given which ultimately worked very well, was to lean the engine to the point that it stops, even at 1/4 throttle.
Then back off until it runs again.
That did the trick for all of my Saitos. All have been incredibly reliable, to the point that I favor Saitos over any other four stroke glow engine...