You can read more about this adjustment on oOples
forum. I got the instructions from "U.S.Cat3K" on the
forum there.
OK, so the main problem is marked with a red circle here. The chassis
of the XX4 differs from the X5, and has some material in the way.
It would not be wise to dremel that away and weaken the chassis.
So we shorten the thick part of the rack brass bushings from 4,8mm
down to 3,2mm.
Also we dremel away some of the front material of the carbon steering
rack.
I also took off a tiny bit of the edges of the chassis, as I did not
want to dremel off more from the steering rack.
Make sure you use screws that are EXACTLY the correct lenght. You
may dremel them down in order to do this.
Mine were too long, so I tried with a shim... bad idea. It then gets
in contact with the lower belt tunnel. It's better to dremel them
shorter.
Put short neck ballstuds on the upper side of the steering rack, and
maybe also secure it with a very small nut (flat) and Loctite.
Finally to take away bump steer you add 1-2 shims on the outer rod
ends. I ended up using 3 (= 2,5mm).
There is still bump steer (inwards), but that's very little.
(This is the same for the X-5)
Mine were too long, so I tried with a shim... bad idea. It then gets
in contact with the lower belt tunnel. It's better to dremel them
shorter.