I simply gave the Simon shop a call today. I couldn't resist waiting any longer. The current owner told me that Mr Arie Simon is now living in Neerpelt, Belgium. Nowadays the shop is focussed on a wider range of bikes for a wider range of purposes, instead of only competion bikes and framebuilding as under Mr Simon. Mr Arie Simon continued in cycling as motor pacer in front of stayers and constructor of the finest dernys you can get. Now at age 78 he is still building dernys in Belgium.
