X12’23 tech tip! Consider this as a supplement to the manual (page 16). One flex option which isn’t mentioned is the one that we (the team) have frequently been using lately. It’s simple – the side braces connected in every spot BUT disconnected from the rear brace. This gives a stiff front end feel, with all the benefits that come with it (more precise and more direct feel) but maintains good side to side flexibility at the rear of the car. The result is a very balanced yet sharp feel. You may try it on any track condition, but we’ve had the best results with it on medium to high grip carpet. See pictures for clarification.

X12'23 users, consider this a supplement to the manual (page 17 & 24). When using 4mm of shimming under the rear center shock mounting point, the 8mm standard ball stud hits the battery quite early, which limits suspension travel (see picture).

When using 4mm of shim there (or less) we suggest using a 6mm ball stud for that option (part number 372650). The 8mm ball stud (which is kit standard) is perfect for when 6mm of shimming is used. The 6mm ball stud was frequently used in previous X12 editions, and many drivers thus may have these at hand already.

In summary:
  • 4mm rear center shock shimming: use a 6mm long ball stud
  • 5-6mm of shimming: use the kit 8mm ball stud

X12’23 tech tip! Recently I’ve seen a few customers having issues with the center shock collecting air through the bottom seal. Unfortunately, this is the result of a tolerance problem in the supplied shock o-ring. A quick fix for this is to add a 0.1 or 0.2mm washer in between the o-ring and the plastic bushing. This will put some tension onto the o-ring which will help it seal better. See picture for clarification.

The shim in this example has part number 964032 (3.2x4.8x0.2).