My brain would have understood wrap some pvc tubing around the frame.
What I might do is get some 1mm thick stainless sheet metal. A piece about 70mm long and wrap it around the chain stays Hahahah,,, and rivet it on.
And when it looks like it might be close to wearing through put a new bit on.
Who knows it ( the chain ) might not hit/scrap at all. I just have to wait and see.
