Thanks for everyone's help in trying to identify the part I was having trouble with. I thought it may have come from the clutch or transmission as those were the parts I was removing and cleaning from the cases before having them glass beaded. Then I thought it may have come from the BS38 carburetors as I was inspecting them before rebuilding them but the threaded end would not fit anywhere. So it must be a stray part from somewhere else and not from the bike that got put in with them by some unknown means..