I'm in the process of my first fixed conversion and have run into a problem, er oppurtunity. I'm using the old hub that was on the 87 Peugeot and I am able to thread the cog on but I can't seem to get the Dura-Ace lockring to thread on. I checked the threads and they are the same, but I think the lockring is smaller than the diameter of the hub. Is this possible? Thanks in advance for any help.