RE: Subtrim? What is it?
goirish - I'm pretty sure it does but check your manual for sure.
foose & goirish- Futaba arms are staggered. Look at you manual. By rotating them 90 degrees you shift them 1 degree relative to the servo. Pick the correct arm/wheel position first and the use sub-trim if needed. This works best with 4 & 6 arm & wheel outputs but also with 2 arms. Again, read your manuals.