I believe my 52 was a "heavy half" from the factory or dealer. I think my frame protectors are made of lead. Never heard of any rubber pc's on the spring ends. After 54 years the spring has worn into the lead about 1/8" Here's a pic.
http://community.webshots.com/photo/377803706/2805825990023244788GtFrcu


1952 1300 Canadian 1/2 ton restomod
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