http://www.youtube.com/watch?v=373R1GpJJqc&feature=youtu.be

What have you set as the gain of the gyro?
You should lower the gain on the gyro and also mechanically by placing the servo ball link on the inner holes.

here:   

Why is the video player not working?

it looks like the gyro gain values needs to be decreased if you have a programmable radio.

Try bumping up the head speed (via increasing throttle curve around the hover points) and/or getting rid of the training skids. 

Look for slop on any of the mechanical parts of the tail (the linkages etc).  Also, make sure the tail control rod is held fairly firmly via the routing guides fitted on the tail boom.

+1 anwar sir, it seems issue with throttle curve, also check slops at linkages, if possible get a updated tail pitch slider mech. i faced many issue with v2 tail so later upgraded to v3 tail, which is a way better.

Finally the problem solved .....
Thanks to Skanda ( RCBazaar) for his help.

No more tail wagging , finally the bird will fly soon.

good, what was the cause please

+1 Avesh. Another Rep addition that does not show, nevertheless, damn good question!

VC sir, few days earlier i just wanted to test my wooden blades that came with the 450 pro. No sooner i reached the mid stick , heli began swirl. Damn my gyro cant counter it. Any reason why.. it is so..

The problem was with the GYRO settings , had to tweek those settings a little bit.

Quote from: avesh on May 12, 2013, 09:56:28 AM
VC sir, few days earlier i just wanted to test my wooden blades that came with the 450 pro. No sooner i reached the mid stick , heli began swirl. Damn my gyro cant counter it. Any reason why.. it is so..

So are you saying that the heli started piroquetting when you reached mid stick and that only happens with wooden blades?

yes , it was so.. really strange..

And she finally has her debut flight !!!!

Quote from: avesh on May 12, 2013, 03:51:19 PM
yes , it was so.. really strange..

Try with a different set of wooden blades ...maybe this set is completely off balance. Or the headspeed of the heli is over wooden blade grade.

Quote from: bhaveshsangani on May 13, 2013, 01:56:13 PM
And she finally has her debut flight !!!!

Congrats! Bhavesh...Keep us posted of the progress

@Hellyflyer thanks, seems the problem is with wooden blades (torque produced).