please tell me if you want me to use something else as the center plate and if the shortening of the arms is wise. i.e. making a mini tricopter .

i have cut down the arms and made them 15,15,15+yaw cm.. also i have cut down the centre frame and made it batman types..lol and also i have painted it
the servo is separate cause i had to remove it while painting the yaw

i think that the weight of the battery is too much (126 gms as specified by the seller)..although i cant lessen the weight of the battery..  any suggestions for bringing down the weight even more?

Your yaw mechanism or the place where the yaw motors sits is bit large you can trim that nearly to the size of the booms but it will lessen only 10-15g not much!

wouldnt make much of difference...
the parts that i have removed
the legs
almost 15cm of wood overall from the booms and everything
10cm of the center plate
some extra zip ties
ANYTHING ELSE?

what capacity battery ur using?

woah!!! i just did the same thing again[ the motor with the prop on it ] and it lifted off at almost 35 to 40%.. this is great !!!!

its a turnigy 1500 mah 3s 20-30c

Did you check the AUW after shortening the arms?

i will tell you when i do 

btw why did you ask me my battery's capacity

I thought you where using a high mAh battery....
Tendency for first timer to get more flight time and thus using a bigger battery...even i made that mistake 

Luckily my motors were capable of handling the weight

i hope mine would be too

How can i attach the servo to the yaw?? The previous method was working but it wasn't smooth. .does anybody have a simple tricopter yaw? Please help me out

though it might be posted in the previous posts, it is always nice to put your motor specs again when you ask for lifting problems

from the picture it looks like the motors are under powered. what is the motor specs.

is your lipo new?  what c rating?

the best way to start is to have a motor of around 700gms lift and the total copter weighing under 750gms and center plates made of cf instead of plywood.

in my earlier version of tricopter, the center plate weight around 140gms and now the cf plates weight just under 45 gms,

that is a great reduction in weight which we will never notice.

reduced weight will aid in overall performance and might smoothen your yaw mechanism.

http://www.rcindia.org/multirotors/my-tricopter-build-from-flitetest/

this is my build thread, see the mechanism, its plain simple and works great.

And it's new..I still have to take the auw. . I think a mini tricopter would do with these motors

My servo is jittering just like this guys... any  solution? ?
https://www.google.co.in/url?sa=t&source=web&rct=j&ei=7nhJVa-QJJPguQShzIC4Cg&url=http://m.youtube.com/watch%3Fv%3DvVpveiMFZbA&ved=0CCIQtwIwAg&usg=AFQjCNFhTlN6ZbV5EspUmyisrkw6NX_mtA&sig2=DyRPzijOyinEfZv3OnNZoA

What type of servo ur using analog or digital?

 i am using hkscm9 digital servo

How are you powering the servo?
What is the amps that the BEC can deliver?

i am directly connecting the servo to fc.. bec can deliver 5v so it still hasnt burned

but there is one problem..
the servo arm becomes loose when power is not supplied..when it is the servo acts like a normal servo
any idea why this is happening?

Looks like the jitter is setting off a vibration that is causing the GYRO to react....
I would suggest you to remove the props and in the code try changing the Low Pass Filter Frequency
Uncomment these one at a time(ignore #define MPU6050_LPF_256HZ as it is a default setting ) and check if any reduction in jitter

/* MPU6050 Low pass filter setting. In case you cannot eliminate all vibrations to the Gyro, you can try
   to decrease the LPF frequency, only one step per try. As soon as twitching gone, stick with that setting.
   It will not help on feedback wobbles, so change only when copter is randomly twiching and all dampening and
   balancing options ran out. Uncomment only one option!
   IMPORTANT! Change low pass filter setting changes PID behaviour, so retune your PID's after changing LPF.*/
//#define MPU6050_LPF_256HZ     // This is the default setting, no need to uncomment, just for reference
//#define MPU6050_LPF_188HZ
//#define MPU6050_LPF_98HZ
//#define MPU6050_LPF_42HZ
//#define MPU6050_LPF_20HZ
//#define MPU6050_LPF_10HZ      // Use this only in extreme cases, rather change motors and/or props