But: A standard FlevoBike/Trike had a shortcoming I didn't want:
... So it was gonna be a trike of FlevoBike.
It had a derailleur and it could not be delivered with my favorite combination of back-pedal brake, hub gear and chain-box.
The reasons why I wanted these: Complete control with your feet, so:
You can keep your arms crossed, even when braking, and minimal maintenance: a closed hub with a completely closed chain-box.
The problem was in the fact that in such a bike you need to have an absolutely constant distance between bracket and hub,
which is not the case in an ordinary FlevoBike: While springing, the distance will increase a little bit.
In case of a derailleur, that increment is compensated by the arm of the derailleur,
but that cannot be used in combination with a back-pedal brake.
Variation number 1: a different front-wheel suspension.
I found a solution that can keep this distance constant:
I moved the hinge around which the front fork can turn while springing, from the top of the fork to a place in the horizontal tube.
At first it took some persuasion to convince Johan Vrielink (the founder of FlevoBike) that this would work,
but eventually he was willing to weld the bike that I had designed and built from card-board. At my own risk.
The final result is shown here:
...and it works!
The new hinge is situated near the red arrow. The frame-part on the left of the hinge makes one part together with the front fork.