new motor = vibration issue.

[AR90]

Well I got my new motor (curtis youngblood next d -8) basically a rebranded scorpion -8.

Along with a 12T pinion, install went fine basically slipped right in.. However when in idle up 90% or 100% the vibes are just INSANE. The tail fin vibrates like crazy probably 2-3 inches of side to side play, it looks like a blur.

You can even see the vibes transferring down into the plastic landing gear, it shakes quite a bit as well.

On top of that, after only 3 minutes of flight, the motor came down extremely hot, at least by my standards. It was way to hot to touch, If I were to leave my finger on it for 3-5 seconds, I'd probably get a burn..

ESC on the other hand seemed just fine.. Any idea what could be causing this?

EDIT: Just for clarification heres the motor and pinion I got.

Motor: http://www.amainhobbies.com/product_...rce=google_ext

Pinion (using the 12t): http://www.amainhobbies.com/product_...13T-Pinion-Set

[jrod155]

Check the bearings

[jimmanyk]

Belt flapping in tail boom due to high speed ?.
I had tail authority issues on my B400, so put in the speedup gear to solve. Later bumped up the throttle curve - headspeed the horizontal fin on the right side was a blur, returned to standard tail gearing vibe gone.

[AR90]

Originally Posted by jrod155

Check the bearings

Bearings seem fine, double checked, even though the motor was brand new.

Originally Posted by jimmanyk

Belt flapping in tail boom due to high speed ?.
I had tail authority issues on my B400, so put in the speedup gear to solve. Later bumped up the throttle curve - headspeed the horizontal fin on the right side was a blur, returned to standard tail gearing vibe gone.

Didn't mess with tail gearing.

[jrod155]

i blew the bottom bearing in my scorpion this morning.

i had a bad vibe in flight, clicking sound, and it was super hot(painful to touch) when i landed. I took the motor apart and the bottom bearing is now seized in there, and the shaft is ruined.

[josefmd]

That's wierd!! You know I have the same motor, and don't have any vib issues!! The motor has been running pretty hot though. It's been pretty hot outside here and on avg I am seeing 105-115 flying it at 100% for 4mins. I screwed up my top bearing whle trying to take the motor apart to regrease it!! Urgh!! I ordered new bearings, retaining clips/washers last night. I had to throw my stock motor back in untill I get it back up and running. I hope you get it figured out!! I really like it in the 450X.

[AR90]

Originally Posted by jrod155

i blew the bottom bearing in my scorpion this morning.

i had a bad vibe in flight, clicking sound, and it was super hot(painful to touch) when i landed. I took the motor apart and the bottom bearing is now seized in there, and the shaft is ruined.

Weird, I guess I will triple check it when I get home and just put the stock motor in for now.

[HFMan]

Try backing the motor off the main gear, and run just the motor... See if you feel vibrations or if the BeastX is freaking out and commanding any movement in the swash or tail. Then reset mesh, remove blades and tail blades and try the same thing. Try to isolate things before swapping the stock motor back in.

[wadders248]

I've just had to repair mine after a power cut-out running a Scorpion -6. Before landing the wrong way up, I was getting more and more tail vibes and with the Scorpion motor it just made it more obvious.

After pretty much a full strip-down, I realised I'd been running the tail blades too loose and the holes have elongated. Running the tail blades tight after the re-build means the tail fin isn't a blur!

[missle]

Did you calibrate the motor to speed controller? I'm not even sure if you still have to do this with the newer generation speed controller, but if so, perhaps that source of heat and over rev = excess vibe at 90 or 100% TC

[FuntanaS]

Get a thicker tail fin.

[AR90]

Originally Posted by FuntanaS

Get a thicker tail fin.

Good idea, ill slap on my 700 tail fin on

Anyways, checked the motor again. Doesn't seem like theres anything wrong with the bearings, everything spins freely and looks okay.. Like I said the motor is 100% brand new.

I think the pinion maybe sitting to low on the main gear, i.e - a part of the main gear rides on the part of the pinion that flanges out. I'm sure that could cause vibes, and I'm not really sure how to get it higher up.

However I don't really know if that explains the issue with the heat.. the motor truly was EXTREMELY hot when it came down.

Any ideas?

[AR90]

So I switched back to the stock motor, just to see if the issue is gone. Apparently I must of not noticed it before with the stock motor..

The vibes are still there, definitely not as bad as it was with the -8, but its still there.. I can still see the fin and the landing gear vibrating quite a bit.

Really clueless as to what could be causing such serious vibes..

[azezeil]

Originally Posted by AR90

So I switched back to the stock motor, just to see if the issue is gone. Apparently I must of not noticed it before with the stock motor..

The vibes are still there, definitely not as bad as it was with the -8, but its still there.. I can still see the fin and the landing gear vibrating quite a bit.

Really clueless as to what could be causing such serious vibes..

I would start with the most likely culprits. Check the main shaft and feathering for bends because even a tiny bend will cause vibs. I'd then check the main blades and tail blades to make sure they're balanced. Give the main gear and tail gear a once over making sure they aren't warped. If those are all fine the only thing left really is the tail pulley and shaft.

Good luck.