John, you need to adjust so that all the slack is out and then about one more turn on each side. Depending on the material you use you may have to readjust again after several flights.

You do need to use ball bearing servos. Do not over tighten. Do not allow the cord/cable to rub or chafe on anything.

Here are a couple of photos that show how I do the pull-pull thing. The yellow tube is used only for a bearing which prevents chafing. By doing it this way, you don't have to make a straight shot from the servo to the horn. The Kevlar cord goes inside the yellow tube and a drop of CA is put into one end of the tube only to lock the cord to the tube.

Ken