I probably explained it poorly. I made a quick picture of the middle and rear part. The seat would be similar to your seat Jürgen. ....at least on the picture. The bottom and main weight is on the pivot. The idea is to connect two pivots (green rods on the picture) in 90 degree angle and then tilted to about 60 degree. The position of the shock absorber (or just a rod instead) would then change the pivot angle.
So far there have been two other proposals for a front suspension: - "python-front-susp-croco.gif" from a russian guy - "front suspension.jpg" from me none of them has been built yet. Cheers, Jürgen.