Question: is the one-piece crankshaft truly an intentional "sludge trap", considering it has no tube?
This whole topic has revealed to me something I am a bit embarrased to admit. I didn't realize that I had a '58 or later crank in my '55 until I reviewed the whole thread, last night. I went to my parts book to see the differences between my crank and Mark's, only to discover that my parts book basically shows Mark's no-tube type and not my own tubed, large-diameter type. Oh well, I guess that's one less link to the hallowed date of birth (the bike's, not mine).
I now think that this glitch in my knowledge at the time of my first rebuild contributed to the big-end failure. I spent endless time studying the exploded views in my parts book, so, never having seen a sludge-trap tube I did not give it due attention and, voila! 3O years (at least) since the last cleaning jumped out to bite me. I learned better for the next rebuild, which, knock wood, has been running great for 900 miles. I also give some blame to the Haynes manual that puts so little emphasis on the sludge trap instead of something like, "HEY YOU, NEWBIE, DON'T FORGET TO CLEAN OUT THE FREAKIN' SLUDGE TRAP!!!!!!!!!"
Richard L.