You need to check your main rotor pitch. The small adjustable ball links that lead from the flybar down to the mixing arms will increase the pitch if you screw them counter clockwise. If you blades are tracking together nicely you should turn each of the two links an equal ammount. You could alternatively turn the three ball links (the three that run from each servo arm to the swashplate), clockwise again turning each link an equal ammount. Both of these actions will increase the picth of the blades.