thanks Bob, so that means you used a neoprene seal directly on the knurl and no leaks? I would have thought that the knurling would roughen up or wear out the seal more and so result in a leak eventually? Can you describe a bit more of your experience? I just checked another forged crank, it is out of a 1971 340, and that also has the knurling, and I'm not sure if the 71 340 had a rope seal or rubber type.