Bad vibes! Do you need boom support brace?

[sharpblue4d]

Went through a recent issue that should the same as everything I've read here but on a belt version. Rebuilt the tail, changed all bearings. Finally gave up for a bit and though again from scratch. High frequency vibes have to be from something spinning fast. Only thing left was the motor. Swapped the motor in from my other 500 without vibes and no more vibes. Put the old motor in the one thats never had a tail vibe and it developed one. Long story short rebuilt the motor and no more vibes. Bearings showed no signs of wear and were silent but obviously something was wrong in there. Never would have believed it if I hadn't seen with my own eyes.

[joecass2]

i tried a new motor this did not fix it. i also replaced the hole tail from the front tail drive all the way back this also did not fix it. so i converted it over to belt drive and this did not fix it. it has somthing to due with the tail rotor. because when i chage the tail rotor the vibration kicks in at a diffrent rpm

[Jotto]

How do you guys balance the tail assembly? I tried with a prop balancer, but it just got worse. I guess I did something wrong.