Some companies allow you to JUST pull off the small gears & turn the arm of the plastic potentiometer shaft to neutral. With the transmitter stick &trim at stop.
The motor speed is then VERY smooth and directly equal to your speed stick movement.
I have don this to many different sized servos.

Servos are THE ONLY ...F & R ESCs ....for 6" to 9 " boats like the Lindburg LCP.