I am trying to do a bit of research on this, and I found in the library a handwritten note that states that it takes 0.125 Liters of "shock oil" with another source specifying Mobiloil 'AF'. If that is true, Mobiloil 'AF' is 40w.
I am sure you already have that, but figure I would get it on the forum for reference.
I am still looking around to find anything else.
Long Island, New York
I have successfully used modern, non foaming, 40w fork oil made by PJ 1 which can be ordered through any bike shop that buys from Parts Unlimited.
Or, you can simply use regular old 40w engine oil.
Technical Adviser, Former owner, Bench Mark Works
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