Now there’s no problem anymore with the drive-train in my velomobile. I ordered a new chain, cassette, and freewheel and Ymte did as usual; it was here two days later! I renewed all the things as soon as the weather allowed me to. And since then I had no problems at all.
So when I was assured that the solution was perfect ; I started to search for the failure …… Johan T. already suggested (in an email) that a little bit of oil in the freewheel whould do wonders. A bike shop in Middelburg did the same trick once with his mango-velomobile and it worked !
I used a lot of IMAL-oil to clean the freewheel from inside and guess what ? A lot of black and hardened grease fell on to my workbench. I cleaned and dryed the freewheel with a lot of compressed air. Later on used a lot of thin oil to lubricate the inside again….. This simpel treatment worked wonderful , so it seems I have a “used, but still working” spare freewheel.
I’ll keep in mind that next October, when I give the velomobile a pre-winter treatment, I must not forget to clean the freewheel again. The not-dissolving is the problem, not the solution. (free to Theo Maassen)