Rudder servo twitching, left side HH mode

[ElektroTrainerS]

Hi,
today I´ve passed my second check flight after changing my swashplate servos from ALIGN DS415M to HI-TEC HS-5065MG. I´ve passed more than 170 nice flights without trouble. Rudder Servo is ALIGN DS520. I´ve servo twitching at 58 % Position (Servo Monitor of GRAUPNER MX-16HoTT) in Heading Hold Mode (50%).
Details from servo Monitor (moving rudder stick from middle to right):
0...40% normal servo, smooth movement
41...56% no servo reaction
57% servo twitching
58...100% normal, smooth servo movement
There is no twitching at all in Normal Mode. Furthermore there is no twitching in both modes (Normal, HH) from middle to the right stick Position.
I´ve removed the rudder pushrod so rudder servo is without any resistance. DS410M Servo Shows the same behaviour on 3GX rudder connector.
Here´s the Video: http://www.rcmovie.de/video/33206c0c104955356eaf

Note: I´ve checked my Receiver by switching into Direct-Mode of 3GX. The rudder servo isn´t twitching in direct mode, it moves smooth as it should in both directions (rudder left and right) the whole servo way

[bad007]

My 550 3GX 3.0 has a twitch on the bench in HH, left input about 75% input but none to the right.
I just say pee on it and fly it. Want a vid?

[nameci]

V3.0 had twitches. I have seen it on v4.0 yet.

[ElektroTrainerS]

Hi,
thanks for Your helpful comments, that´s exactly what an experienced RC Pilot told me on Friday. Today I´ve adjusted the pushrod in normal mode (middle Position of tail pitch cartridge). After that I´ve adjusted the endpoints (Limits) in 3GX too. Today it was a bit stormy, but tomorrow I´ll do some further check flights. Last Friday the behavior was nice in flight. The tail just one time turned 10...20° to the right side during takeoff.

[Van Scott]

Originally Posted by bad007

My 550 3GX 3.0 has a twitch on the bench in HH, left input about 75% input but none to the right.
I just say pee on it and fly it. Want a vid?

Yep. Both my units do same on the Bench & fly great.