Wobbles at 1800

[Cadriel]

Hi all,

Few more test flights under my belt.

I have some severe wobbles at ~1800 RPM. I've tried 1750, 1850 and 1800. All cause sever head wobbles. At 1600 its fine, and 2000 its fine.

I tried dropping cyclic gain to 30 with seemingly no effect.

Anything else I could try bar ripping the frame apart again? Or just fly at anything other than the above headspeeds?

[flyer2160]

Hi,

I have had the same trouble, Try changing the main blade bolts slacker or tighter this can have an effect.

Also search this forum for wobbles over 1800 rpm people have tried many things as i have myself. I dont think there is a definative answer

Andy

[Lighty]

The dampers need bedding in that's all. Give it 20 or so flights.

[Rockarruda]

I had loosened my tail rod guide. Others have done this as well, but so loose that it rattles, just small adjustments until it stops shaking.

[snaaakeey]

I would say the majority of 1800-2000 rpm wobble issues are dampers but there is a wobble I have see and experenced myself and has been reported on alot that you just cant get rid of. A few have sold the heli because of it! My personal exp is this

Maiden wobble like yours. Backed of one of the pots on the beastx and it went away. Waited till the dampers bedded in and then I could turn the gain back up.

Had an crash right on the head and must have bent the head center hub ( could not see it by eye. Lots and lots of time spent vibe hunting). Ran out of ideas and exchanging parts. Eventually tried a new center hub and perfect. Recently put new dampers in and no vibes at all.

I personally know 2 pilots who went through every piece on the heli exchanging parts with the shop and no matter what they tried the wobble never went away.

hope yours is dampers! good luck.

[Stolla]

I dont recall if the compass has bolt through the head as well as the split lines with bolts to tighten to shaft but if so try first tightening the slit bolts then main bolt or vice versa, i had a problem with my e8 where you could easily see the head tracking was out when running on bench no blades, the procedure solved it. My compass had no wobbles anywhere but i lubed the dampers and blades were not too tight.

[Cadriel]

Thanks for the replies all.

I pulled the head apart, lubed everything - lubed the dampers - and re-seated everything during the build.

I tightened the head to the shaft in the way you described initially Stolla - so I'm not sure its that.

Blades are as I always do them - tight enough that they dont fall when held on its side - but if shaken they drop.

I even balanced my tail. I'll see what loosening the tail rod guide does.

I'll also give it a good 20 or so flights and see if the issue goes away. Hope it does - not a fan of chasing rogue vibes down

[Jeff_Barrett]

I run 1850 frequently without issues .... make sure you slather clear synthetic grease on the inside and outside of the dampners.

Try tightening your blades a little more ... I run mine a little on the tighter side now.

[GimpyGolden]

I had this wobble early season after a rebuild. Flew above that head speed for ~20 flights and it sorted itself out.
Now fly between 1850 and 2350 with no wobbles.

[Cadriel]

Alrighty - I'm going to let her settle in for a bit and see how things work out.

On another note - what size batteries are you all running? I have some older GensAce 4000's that I'm running at the moment in my X5 that I use.

Now looking at other options.. and I want something I can use between both heli's.