In a HH gyro, throw limits are NOT set by ATVs, the ATVs only affect the maximum commanded piro rate (The "Angular Velocity" part of the "AVCS" moniker that Futaba uses to describe it's HH gyros . . . ). The gryo itself limits how far it can make the servo travel to attempt to fulfill that command. From looking at the GY240 manual, it appears, unlike the 401 and above, to not have an adjustment. As such, the way to get it setup correctly would appear to be to use a servo arm that will allow the pitch slider to make full travel. When a heli is sitting on the ground, and you give it left or right rudder, no matter what the ATV, in HH, it will go to full travel in the specific direction, in an attempt to fulfill the yaw rate command. If you don't beleive this - try it . . . .