Von Ohain

Hi!

I got a HK 500 GT, and has a problem with the helicopter oscillating around both cyclic control axes.
First I assumed it was due to a bent shaft in a crash, and didn't care too much about it.
Now its getting worse, i have a completely new head, and my friends brand new HK500GT has this same issue aswell.

Does anyone know what the problem is, and a possible fix?

The only thing I can spot in the head to be different from the original Align T-Rex is that the paddles of the HK500GT is extremely small.
Smaller than 450 helicopters that i compared with.
Can this be causing the problem?

augerin2

Try cking the balance on the head itself, I have had the same issue with a HK450 head V2 I recently purchased. The head was fine @ first then it begain to vibrate especially inverted. When I went back to the original Trex v1 head viola vibration was gone. The vibration eneded up causing a minor crash,, a ball link conector broke.

Rob2160

What is your Rotor RPM Speed? How tight are your main rotor blades?

Von Ohain

Head speed is 3100 rpm.
Blade tightness: not much.
I believe blades will sling out and straight with no problem at all.

Von Ohain

I think I solved it.
Threadlock had gotten into one of the main blades thrust bearings (thanks to my own carelessness), making that bearing a bit slow.
The oscilations is gone now that I replaced the bearing.