N5c jumps up and down

[Benysjets]

 I am looking for some advice.
I bought a used N5C belt with OS55hz and was getting a bad vibration.
What I have done all read
Rebuilt motor new front and rear bearing.
New clutch fan shroud and fan also balanced them.
Updated main shaft to 10mm straight shaft. Installed new bearings for shaft as well.
Replaced spindle and dampners.
Also has a new tail shaft.
Also new BK 7002 cyclic and new throttle servo.
After replacing all that the vibration got better. Enough where I could take off.
Before take off the Heli vibrates up and down. And even jumps off the ground a bit before it takes off. I’ve never seen this happen before. And don’t know what to try next. Looking for advice what to try next to eliminate the vibration.
I did notice when I spin rotor by hand I can feel main gear and pinon mesh together even in the boom. Is this normal.
I have a very small lash between gear and piñon and spins freely.
Sorry for long post just trying to give a good explanation. Trying to paint a clear picture. Any help would be appreciated.

[Rodney Kirstine]

Welcome! 

When you installed the new dampers did you grease them really good inside and out?

[Benysjets]

I did grease them.
I got some new bearings for clutch stack went ahead took motor out and cleaned and rechecked everything.
Seems the up and down is gone the vibration is pretty much gone. Thank god.
Now I have a twitch in the tail lol. I’m gonna go fly today and try to see if I can tune or program it out.

[Rodney Kirstine]

Well, that's mostly good news then.