"I have to disagree. Having the bellcrank and the rudder horn the same size will offer a 1:1 ratio. It is desireable to set your system up with a 1.5:1 ratio giving "mechanical advantage" to the setup. I have mine set up with a 3" servo arm and a 4.5" rudder horn."

the setup you describe gives you mechanical "disadvantage".... slop is multiplied and torque is reduced...

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