I know that they quit using the "Open C" in something like '58, but Hilary
Stone has just surprised me with the mention of a "Loopy L" on the
derailleur he is offering for sale on E-Bay right now. Item # 130137404580
for those who would like to look.
What were the dates for this rather loopy letter? When did the "Open C"
come into use? Were there other strange letters we should be aware of?
Lansing, MI USA