Well okay, after having a headache about this, i finally found out ur not supposed to bind the collective lower(analouge) to any axis, but bind both axis to collective raise(analouge) so it uses the full range of ur joystick.
But still im having a problem about the slow turning speed which seems to be occuring with all kind of joysticks, even my logitech g27 pedals, the Saitek X52 Joystick z axis and also my xbox360 controller.
Its only working correctly with the correct speed with my defauklt key bindings "del" and "end"
UPDATE:
ok, although nobody here even replied i finally found out there seems to be a problem if im using the Logitech g27 pedals with my Saitek X52 controller.
Therefore i had to unbind that one, just simply as that .....
Just wanted to share if someone is dumb enough like me, trying to find out for a week what the problem could be ....
SOLVED