So I have created a custom mob, with its own model and rotations, but these rotations only activate while the mob is walking/wandering. How can I have the mob perform them while it is standing still? Right now I've just got some test rotations:

 public void setRotationAngles(float par1, float par2, float par3, float par4, float par5, float par6, Entity entitypar7) {
        this.Block26.rotateAngleX = -1.5F * this.custommotion(par1, 13.0F) * par2;
        this.Block13.rotateAngleX = 1.5F * this.custommotion(par1, 13.0F) * par2;
        this.Block13.rotateAngleY = 0.0F;
    }

 So for starters, I'd like block26 to constantly do its rotations, while the mob is standing still. Is there a way to accomplish this?

You can calculate your rotation angles using any other variable. For example the amount of ticks your entity has existed for.