From: fortunati.luigi@gmail.com   
      
   One possible explanation for the direction of the precession is that of   
   my simulation   
   https://www.geogebra.org/m/ry8zxkwj   
      
   Gravity affects impulses in diametrically opposite ways if the direction   
   of rotation changes.   
      
   If the rotation is clockwise, the impulses of the right side of the   
   wheel are strengthened by the force of gravity and those of the left   
   side are slowed down.   
      
   Consequently, in the lower part of the wheel the impulses are at their   
   maximum, and in the upper part they are at a minimum.   
      
   Therefore, it is the direction of the impulses from the lower part of   
   the wheel (going to the left) that prevails and the precession goes to   
   the left.   
      
   It goes without saying that if the rotation is counterclockwise, the   
   exact opposite occurs and the precession goes to the right.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)