[>:] I have a Shogun V2 and I need help with a tail vibration. First can I say I also have two other helis - A Dragonfly 35 and a Shogun V1 so I have had experience with setting up and balancing. I bought this V2 heli around christmas when Hobby People had them on sale for $99.00. I stowed it away in the closet until I could buy enough pieces to put it together without taking my other helis appart. That time is now and right out of the box this has been the biggest piece of f$%^&&g junk I have ever owned. I am sure when I get it finally built I will be happy. Out of the box the blades are supposed to be balanced but one of them is too far out to balance with tape. I spooled the heli up and it had a SEVERE wobble on the head. The blades were the problem. A new pair of blades and the head vibration is gone. I noticed the tail vibrates and the tail blades do not track the same above 1/2 throttle. That is when the tail boom, fins and everything else on the boom vibrates. It drives the gyro crazy. I removed the main blades and paddles to aid in diagnosis. I removed the boom and ran without the boom and there is no vibration, nice and smooth. I have tried to run with the belt loose and tight and everywhere in the middle. I also tried the clock position of the tail case assy to try and affect the position of how it rides on the pulleys. At one point I was holding the gear case and the vibration vent away and I let go of the case and it was gone until I cut the throttle and re-applied. I have replaced the following parts. 1. Drive belt. 2. Tail boom. 3. Gear case. 3. Rear axle and rear belt gear. 4. rear blades and checked the balance, I also used the ones from my V1. 5. Main drive gear because it was warped. 6. Blade grips. I have tried putting tape on the tail boom under the rear case and under the blade grips. The vibration is still present. When the heli speeds up it sounds exactly like an old pager going off. That is the closest description I have. I have read the posts in this forum and others looking for an idea of how to cure this but as of yet I am discouraged. If I don't have a resolution then saturday after work I am going to take to the local flying field and look for help also.

Any comments either negative or positive will be greatly appreciated. all I want to do is FLY my new heli. If its a mistake I have made or overlooked then please feel free to let me know.

To the Administrator, if I have posted this in the wrong plase then could you please move it to the correct area and I appologize for the inconvenience.

Thanks everyone,
Astra

MrAshTray,

I have one new V2 I fly and it absolutely awesom, I also have a V1 I flew, but then converted to a V2 flies great as well. I remember reading somewhere that they are famous for the vibration. One thing you didn't mentioned you changed was the spindle shaft. If it's bent it cna cause a wobbling or vibrating. This may be a dumb question: Are you sure the belt isn't twisted? It's hard to tell.

Where do you have your gyro mounted?

Mrashtray
I also have the Shogun 2. I am also working on getting out a vibration, But it's a small vibration and also at this time appears to be in the tail. Anyway something you may want to try. I read a post sometime back where a guy had a similiar problem as yours.
The guy said that he finally got it solved by moving the tail boom supports. I cant remember if he lenghted or made them shorter, but he claimed it got rid of the problem, (Resisdence Vibration).

HeliTB Thanks for the reply. I have changed the main axle and I rolled the old one on a flat surface and it was not bent. I know the new one is good also. I also changed the rear axle shaft as well.

Thanks,
Astra

DVI Thanks for the reply. I have only moved the rear vertical fin fore and aft. There is no effect. The vibration is too severe to even cancel while holding with your hand.

Thanks,
Astra

That's really sounds like a bent shaft to me. Whether it be the main shaft, spindle shaft or the motor shaft.

start by taking everything off the tail except the gear case and shaft. Check fit of shaft in bearings. Spool up slow and look for wobbles in the shaft. Increase speed and check for vibration. Add parts back to the shaft one at a time and repeat vibration checks for each part.

HeliTB I agree with what you are saying but I have confirmed the main shaft, axle shaft and motor shaft are ok. When I replaced the belt I looked inside the tail boom and made sure the belt was not crossed or twisted. The new belt did not help. I have ran the tail belt tight enough to produce gear whine and I have tried it loose enough that the belt almost slips and almost everywhere in between. In both cases the vibration was there but it changed as to what rpm the vibration happens. At lower rpms there is no vibration. It is amplified when the rear blades are installed.

Thanks,
Astra

Karyn are you talking about a shaft driven tail or a belt driven tail. If you are asking about the rear axle that drives the rear blades and rides in the gear case then yes I have replaced the rear axle twice. The only thing I have not checked was the rear case axle bearings. I will check those when I get home tonight.

Thanks for your reply.
Astra

How tight are your main blade and rotor blades? This can cause vibrations as well.

HeliTB I don not have the main blades on at this time so it is easier to run. I do not have the paddles on the flybar either. I have tried having the tail blades tight and loose. The vibration is in the tail boom and back. I know vibration can travel but with the boom off it is SMOOOOOOTH.

Thanks,
Astra

Did you say that your blades are not balanced? If so, that can cause it. Also if your blades aren't track properly that could cause the vibration.

HeliTB Tonight I switched the tail case bearings from my V1 and installed them on my V2. They seem to fit tighter. I also slid the tail belt gear a little to the right to result in moving the shaft more to the left. I used the tail rotor hub from me V1 because it fits tighter on the rear axle and the blade grips fit tighter on it. When I put everything back together (still having the main blades and paddles off) it was acceptable. The rear blade tracking was right on!!! I put the main blades and flybar paddles back on and spooled the whole thing up. NO vibration from the tail. The gyro acted normaly and I hovered the heli. Now it's off to finish the setup.

The only conclussion I can come up with is there was too much play with the tail rotor hub and blade grips. Even though the parts are supposed to be the same but they didn't fit the same. I sure couldn't tell any difference when I looked at them. What I am going to do is save up some money and replace the tail and main rotor assemblies with cnc ones. Until then I will fly as is. I want to thank everyone who replied to my cry for help. I appreciated your thoughts and it was nice to have another point of view.

Thank You.
Astra

Glad to hear you resolved your problem. Have fun...