musterpilot

Hi all need some help please
I have a 600 size longranger that I am flying
I live in the bush in Western Australia so not much of a chance of advice
this is my setup

tt raptor 50 mechanics
ys 50 st motor
gi gov
Futaba 401 gyro
Jr 539 servos

expo 30% on all channels
throws 60%
head speed 1250 rpm
do I have to mix any channels ?
The hele flys ok but seems a bit twitchy on all axises
thanks for looking hope someone can help

John