Hi,
I am kind of new to RC heli's. I am setting up my Trex 450, and have an odd problem that I cannot fix.

I think theheli is set-up (I have it fixed to a moving 'wheel' so i can power up, spin it round, look for vibrations, set gyro etc...... This looks generally ok
No apparent missalignment, or vibration (see below)
Gyro seems set-up ok

The problem is that at about50% - 60% throttle the heli (sometimes!!!) begins to sound different i.e. I can hear a low frequency 'beat'. Also, the tail starts wagging (No rudder input). If I add more or less throttle the problem appears to go away.............. i.e. it appears in a specific band, and dissappears outside of this band.

I cannot solve this, any tips very greatfull.


Thanks
Phil

You'll need to post a video. Not certain I understand the problem. What kind of gyro are you using? What gain? What tail servo?

Hi Again,
gi1mo2 and anyone else who read this..........

I think I found the problem, the belt to the rear rotor was loose and slipping; the tail would instantly drift andthe gyro compenstes (hence the wagging).

Is there any guidelines as to how tight the belt should be?? Align manual says 'lightly tighten'

Regards
Phil

I normally apply light finger pressure and the belt sides shouldn't touch.