How much do they move? If only a tiny bit, I know that Cleanflight was adding a bit of pitch movement to compensate for raised throttle - is that a possible issue? If that movement is very small, that may be it, otherwise:

Did you set the model to wing in cleanflight/betaflight?
Did you check for correct resource address of motor 3 and 4?
Did you clear the resource address with 

Quote:resource motor 3 none
resource motor 4 none

before assigning servos?
What do you have set on your radio? Keep in mind that the FC should take care of all mixers etc, so disable those on the TX.

XRacer 3.1, BF 3.1.7

In the CLI, resources before:

resource MOTOR 1 A06
resource MOTOR 2 A07
resource MOTOR 3 A11
resource MOTOR 4 A12
resource MOTOR 5 B08
resource MOTOR 6 B09
resource MOTOR 7 A02
resource MOTOR 8 A03
resource MOTOR 9 A08

Resources after:

resource MOTOR 1 A06
resource MOTOR 2 A07
resource MOTOR 5 B08
resource MOTOR 6 B09
resource MOTOR 7 A02
resource MOTOR 8 A03
resource MOTOR 9 A08
resource SERVO 1 A12
resource SERVO 2 A11

I also reversed Servo 4 (-100%) in the Servos tab.

Working fine, but when throttling, the model will be incontrolable.