Just a couple of thought on the last two posts, my Messerschmitt has rubber in compression suspension and if you took off the shock absorbers it would be undrivable. Just thought of a few more vehicles that use nieman rings, Isetta Velam, Avolette, Bernadette scooter. I think the unusual design of the swing arms on the klienwotsit is probably because the tubing used will be very thin to save weight, my Inter likewise has a over fussy swing arm for the same reason, remember it was aircraft engineering design that went into many of these babies. Chris, being an X Remorque Franc trailer owner do you know if the rings are still available anywhere in the UK? I sent to France for the last lot and paid an arm and a leg.