Split rear topdecks on the front (XRAY X4).

You may have noted a new trend for the flex settings of the X4 platform. First of all, the widespread use of the optional split topdecks, both on carpet and asphalt. But I want to highlight and explain the use of a rear split topdeck on the front of the car, and the different options that come with it. See a detailed description to the picture here:

  1. This is the regular front split topdeck (301072). This is the softest option. The car will have a lot of front grip, but can sometimes feel a little imprecise and/or difficult to drive, even with 2 shoulder screws mounted.
  2. This is the regular rear split topdeck (301073), which also fits on the front of the car. Without cutting it, it tends to be a little stiff for most conditions. The handling will be very predictable and precise, but the car will usually lack front grip.
  3. When you use the rear topdeck on the front, try cutting the furthermost front bridge. This will allow the topdeck to flex a lot more, which will increase steering on entry and mid corner. This option is still stiffer, more predictable, and more precise than option #1, but more aggressive than option #2.
  4. The other option which has been very popular within the team is to cut bridge number 2 and 3 (as indicated in the picture). This moves the flex point further down on the topdeck, which seems to give better mid corner steering than option #3. This particular option was used by myself and Bruno Coelho at the recent Snowbird Nationals.
Feel free to try these different flex options to fine tune the handling of your X4! We've had very good success with this on medium to high grip carpet. We are yet to try these options on asphalt. But I can definitely see them being useful on high grip asphalt, for example, indoor asphalt.


A. Hagberg