ORIGINAL: Razor-RCU
It is normal if the shakes are minor...
One time when I did not have an OS-F (
recommended highly in the YS-63) I used an OS-8 (I think?) and it ran very rough! What plug you runnin'?
Also, make sure your prop is balanced-(probably not the problem but contributes-)
Yesterday I had the idle down to about 1850 just for kicks and ran a 12x7 @ 11.6K
I'm using an Enya #3. It was highly recommended by someone here. I can't remember who.