ok i have trex and a specktrum dx7 remote and the tail keeps whiping no mater what i do ive adjusted the gyro went through all my set up and check settings in the remote but i dont know whats wrong can somone please point me in the right direction

What do you mean by whipping?
If it is wagging back and forth your gyro sensitivity is too high.
If it wants to spin in one direction it is possible that your servo, gyro or both need to be reversed. The servo gets reversed in your transmitter the gyro should have a direction switch on it.
Another possibilty, your tail rotor is turning the wrong way (belt on wrong) or your tail blades are on backwards.

Missleman covered it all, but just to reiterate

1) In rate mode, and servo initialized - Servo horn to link needs to be 90deg, slider arm to link needs to be 90deg and slider need to be midway between both extremes.
2) If you jerk the heli anti-clockwise (opposite to rotor) the tail servo should twitch towards the tail. If not, then you need to reverse the Gyro switch.
3) Left stick rudder should make the tail servo twitch towards the tail, if not reverse the servo on radio
4) In HH mode, setup limit on the Gyro and ensure there is not binding at full left and right rudder. The rudder ATV's only control Piro rate and not the actual limit in HH mode, so this is important.
5) Most important, make sure the tail slide hub screw is tight and holding on the slider pin. Use loctite to fix the hub, so the hub is slightly outside the pin. I lost control of the tail because of this simple mistake.