vibration from nowhere???

[scooby61]

first i love my 600n its my first nitro and its an amazing difference from the 450. but i just ran through my fifth tank and suddenly right about when you get headspeed up to lift off the ground the tail shows a vibration that is rapid and bad enough to make the vertical tail fin just whip back and fourth i didn't have this problem the first four tanks. an experienced nitro freind of mine test flew the bird for me on the fourth tank and almost ran it out of fuel because i have it so rich on the new motor. when he landed it i noticed the vibration and ever since then when i go to lift off.
I've checked every bolt for looseness, rebalnced the blades(they were fine anyway), backed off the gyro gain, added gyro gain, recentered the tail, leaned the motor , richened the motor, i thinke the tail belt tension is good but i don't know whats too tight i'm only guessing, any one have any ideas where else to go with this i would greatly appreciate it.

[jet22b]

Hi scooby61;

What headspeed are you running on your 600N?? I had the same vibration on my 600N untill I back-down on the head-speed. Now my head-speed is 2100 RPM and no vibration!!
Maybe this will help you on your 600N

jet22b

[scooby61]

i don't have a tach but the same freind of mine has one i think he said i was running about 1920 at hover. let me add more info its a 600n standard with 401 gyro and os 50 hyper, no gov.

[erniefritz]

seen this before , possibly because your soooo rich the engine is studdering causing the Vibe , once you start leaning the engine out the Vibe will go away, also make sure your tail blades are not too tight , they should be able to straighten under their own weight during spin up...

[raptordave]

I agree a engine too rich will cause this vibration

[scooby61]

thanks folks i'll try all that later its dark here now. atleast i have somewhere to look.

[Mike3DPro]

I had the same exact tail fin wobble. For me it was just blade tracking. Once I got it, it was solid. Then 2 flights later, somehow IDK but the tracking was a little off again, so I fixed it, and again it was fine. Does tracking ever change if you don't crash or anything? I guess I may have not got it "perfect" the first time.

[Swiss_Rex]

First of all hello to everybody, I am new to this forum. After a few years with Kyosho's Concept 60 I changend to the T-Rex 600 Nitro.

I had the same problems with a strong tail fin wobble. As already described I tried every thing .....

Finaly I changed the (nearly new) main shaft and :happyd everything was fine!

So please check also a fabric new main shaft and after a while of vibrations also the bearings ....

Regards from Switzerland

Otto

www.mg-nussbaeumli.ch (http://www.mg-nussbaeumli.ch)

[mewsikman]

its really simple, i had the exact same problem its not mechanical just the battery, if you get a full charge on your battery it wont do it anymore, all that it is the gyro servo is twitching because of low voltage.... try it again with a fully charged battery and see what happens... if it still does it then look at mechanical side of it