VIBE RATIONS !!! OS 55 PROBLEM ???? THE VIBE HUM ? HELP Please !

[Steve]

Well, curious as it is with your heli, I've just changed the engine in mine this evening. It's had the same Align 50H in from new with an MP5 (was also new) from the day it was built 3 years ago. It's never been crashed, never had a bearing cahnged and was as silky smooth the last time I flew it as the day it was built. I've just fitted a YS56 and Hatori 566 pipe and have deliberately paid no attention to dialling the fan hub... just bolted it on. The point being that I never paid any attention to it when I first built the heli and have never had a vibe issue other than when the torque tube bearing failed. Tonight is the first time that Align engine has ever been out of this heli I think.

So hopefully I'll get a chance to try the new motor tomorrow and see if it vibes - will report back. Not sure if it's a useful post, but you can draw your own conclusions from the results maybe.

[Mr.Brown]

What is.. dialing in the hub[QUOTE=Steve;641996]Well, curious as it is with your heli, I've just changed the engine in mine this evening. It's had the same Align 50H in from new with an MP5 (was also new) from the day it was built 3 years ago. It's never been crashed, never had a bearing cahnged and was as silky smooth the last time I flew it as the day it was built. I've just fitted a YS56 and Hatori 566 pipe and have deliberately paid no attention to dialling the fan hub... just bolted it on. The point being that I never paid any attention to it when I first built the heli and have never had a vibe issue other than when the torque tube bearing failed. Tonight is the first time that Align engine has ever been out of this heli I think.

So hopefully I'll get a chance to try the new motor tomorrow and see if it vibes - will report back. Not sure if it's a useful post, but you can draw your own conclusions from the results maybe.[/QUOTE]

[Steve]

[QUOTE=align;642032]What is.. dialing in the hub[/QUOTE]

Using a dial gauge to minimise the runout on the hub assembly - i.e. trying to make sure it is located as centrally as possible on the engine to minimise vibes. When the engine is spinning at 18,000 rpm a runout of a few thousands of an inch can cause serious vibrations.

[forbsy]

I don't have mine dialled in either.When i was chasing the vibe i did think this might be the cause.I think i did flip the clutch 180 degrees though.I have bought a dial guage,all i need to do is by the stand for it!Mine is running on the safe side as barely run in the os55

[rachel]

An update,

I flew Vicky yesterday and ,..... she's better , not fixed but better . The vibe before the clutch engaged was much better and improved but slightly ritchening the idle mixture.
I also found that this enabled me to drop the idle speed which definatly improved things.
The humming pulsing sound in flight was still apparent, which I am sure is drive train related, maybe main gear mesh but this only occured at a very high headspeed.

I then tuened the top end mixture and midrange as shown here,

[url=http://www.helifreak.com/showthread.php?t=276520]Nitro Engine Tuning 101 - HeliFreak[/url]
a very usefull video which really helps.

I will keep refining the Vibe and report on my progress.

Once again my thanks to the Steve's & all who posted / helped .

Hugs all thanks Rachel

[Steve]

Any further forward with this?

I've been running mine now for a couple of weeks with the new engine and it's ok. Not perfect, but ok. The previous Align 50 was super smooth and I've made no effort to dial the fan hub assembly on the YS56 but I wouldn't say it's vibing bad. If I spent an hour really tweaking it up, I'm sure it would be great, but to be honest, it's not bad enough to worry about.

I can't see that the hub/fan is the cause to be honest. Of course it always helps to get this stuff right, but it's not making that much of an effect on mine.

The engine is going great.

[rachel]

I span the clutch through 180 degrees on the hub and that really helped :) but what can I say I love flying the heli and practicing flying to some music last weekend the FBL Vibe really rocks :)
However the same vibe throught the tail fin is still as bad as ever, it's really annoying and ruins a nice heli :(
Do I just cut and run and sell Vicky or should I ask someone else to have a go at dialing in the hub ?

It's such a shame maybe I should have just followed the herd and bought a t rex 600 :ack2:

I wonder if Jr would like to sponsor me for a new Vibe nex ?????? I doubt it but hey a girl can dream. :(

[NEAGRON]

No Rachel,dont sell "VICKY",for sure if some one buy'sit and solves the vibe youll be kicking yourself,what about trying a differant position for the bearing's on the torque tube to see if that cures it,and finally as you say you enjoy flying "VICKY"so no adoptig her she's your baby.
All the best,Marty.:hat: