ECO 16 shake on throttle up

Not new to helis but new to electrics.
Just purchased used (crashed) ECO 16 with lots of upgrades.
Replaced many broken and bent parts that came with purchase.
ECO 16 came with Phasor 45-3 motor, 40-3 P opto ESC, auto hub, alumi swash, alumi rotor head, glass blades, alumi motor mount/frame piece and others.
Replaced all bent and or broken parts ie; main shaft,blade bearing shaft and tail shaft.
Followed set up instructions and checked links.
began throttled up and severe wobble began and was unable to throttle through it, tail boom strike.
Checked all again found nothing "out".
Blades are balanced.
I have flown helis before and did not have this type problem. Have built Cobra and Robe Mosquito and flown after building did not have problems like this, maybe tracking and trim but never boom strike.
Has been about 6 years since I have flown but have 200 plus hours on flight sim recently.
Have read your notes for a few days and found lots of helpful info. Have tried several times to throttle up but cant get through this wobble. Does not do this without blades.
Any suggestions would be appreciated.

Hello lbs and welcome to the board. [img]/ubbthreads/images/graemlins/smile.gif[/img]

First thing to check, how tight are your blade bolts, they should be just loose enough so that if the head is horizontal they will just fall under there own weight. When I was starting out and getting the heli trimmed and balanced I ran mine a bit tighter than that and it hovered fine.

Gary

Thanks for the reply;
I have tried several blade tightness adjustments, no change.
My phasor motor has a rather abrupt start so I am limited to how loose i can set the blades.
The one time I tried to throttle through it I had a tail boom strike and cant get to hover point.

[HARRomeo]

The only time I ever had that severe vibrations when throttling up was when my blades were too tight. Maybe some of the veterans around here have more ideas for you. [img]/ubbthreads/images/graemlins/frown.gif[/img]

Welcome. You and I are some of the few that fly 16's and not 8's (not that it matters). I can almost guarantee that if you pull your rotor head apart, the shaft is bent inside the head. I had the same thing, wasn't visible to the eye when I looked at the head, but upon pulling the head apart, I noticed the shaft was bent. Check it out.

The feather shaft was one of the first things I replaced.
This is the third feather shaft and third main shaft and second boom replacement.
I have built several helis for myself and others in the past and have never had this kind of problem.
I've been working on this thing for over 3 weeks (daily) and have not been up to hover RPM without major problems.
I changed to the stock plastic head and it was worse.
I've spent over $200.00 replacing parts that came with the heli that were still in Ikarus bags when I got it.
I am very frustrated at this point and have new parts on order AGAIN.
I've read several posts on this site with info on this but no progress yet.
Thanks for the reply.
I will try all new parts one more time.

[Luxor]

Just one more idea. Are the feathering shaft bearings OK. One bad bearing cause this type of vibration also.

I first found two bearings with very slight roughness and replaced them.Can't feel any rough bearings now but have ordered new ones, shaft, main shaft and other parts to try ONE more time.
Thanks

[BertVK]

I know you already checked this but make sure your rotor head is balanced and that the blades are balanced and straight.
I'm going over my rotor head now for an article and I'm amazed that even though the heli was only vibrating very lightly I can still seem to balance things better.

Could be the dynamic balance of the blades is out have a look here
HeliFever.Com

Hope it helps

G.