Hi asumi,
the cardan and gear box need a small backlash (0,2-0,4mm) , otherwise you will have excessive wear in the transmission part if the gear wheels are very close together. The rear backlash is adjusted by a round shim in the cardan. The front backlash is adjusted by an aluminum washer foil.
http://xt1200z-forum.de/viewtopic.php?f ... ash#p23254" onclick="window.open(this.href);return false;
In the following video you can see how the backlash of a gear box (e.g. cardan) will be masured:
https://www.youtube.com/watch?v=r0NsMzdFcZg" onclick="window.open(this.href);return false;
Due to the multiple redirection of the transmission (front/rear backlash; gear box backlash), the different backlashes multiply to a total tolerance of your described
5-7 cm tolerance in the wheel.