yup, no prob. I am taking about the tail rotor. How you balance it is so that one prop is on one side and the other prop is on the other side (this is the blade off of the tail rotor). The knife will be at a 90 to the blade, and you will just get it on there so it balances (think like a see saw or something). It's harder to find the balance point on these small heli's, and it will probably fall off if you've got it wrong. But you want it to balance when the sharp blade of the knife is right in the center of the hole where it goes on to the motor.

Also if you'ev got the wild wheels it comes with 2 props. Put the prop on with the circle around it, which is the smaller one. It has better balance, and the bigger one doesn't really add performance (even though it should)