Originally Posted by
Fergup
The one confusion I had was the difference between the Steering Speed (SPD-TN_ and the Steering EXP( EXT-ST)
Steering speed is the rate at which the servo moves throughout the entire travel.
Steering Exponential is the adjustment you make for the sensitivity at neutral or centered. Negative Expo ruduces the sensitivity as you start moving the wheel it retards the steering slightly as you begin to move the wheel off cente and give full steering the end of the wheel throw. Positive Expo will give greater steering with slight wheel movement from center.
The 9551 is not the fastest digital servo out there and as Kenji knows that it is the same speed as the analog JR Z590 so it's speed shouldn't be an issue.
Perhaps you are so used to a very slow weak servo that you were over compensating to control it and now that you have a decent mid-speed servo you find that it is more responsive and reacts to your tendancy to over control habit you picked up with the old servo.