Unless it is excessive, you do not want to get rid of it. You have positive Ackerman (a desirable trait for pull-pull). As mentioned above, it is a matter of geometrythe relationship of the hinge points relative to where the pull-pull lines are attached. Google "Ackerman" and delve through the list for where it applies to RC for more info. You may even find it if you do a search for Ackerman in these forums. Without some positive Ackerman, you will strain your servos and could even cause problems in excessive current drain at high surface deflections, even worse, negative Ackerman and you will have some Ackerman effect unless you managed to get every hinge point and attach point absolutely perfect (an almost impossible task).