Originally Posted by
Gonzo Bob
Dura-Ace 7400 hubs had a different freehub attachment method than other Shimano hubs and accept only Dura-Ace freehubs. But I don't think a Dura-Ace 7-speed HG/UG freehub was ever made. Dura-Ace was 8-speed by the time Shimano introduced HG and the hard-to-find Dura-Ace HG/UG freehub is 8-speed. If your freehub is only 7-speed, I don't think it is Dura-Ace. If your hubs are Dura-Ace, I have no idea how someone put a non-Dura-Ace freehub on an old Dura-Ace hub - could be it's just held in place by the axle.
It's hard to tell which model hub that is, but it very well could be a 7400-series hub that had the freehub-body replaced. At the time, there were 7-spd bodies available in UG/HG or HG-only versions. These went on the 600EX hubs and featured the same screw-on attachment as the Dura-ace.
rothenfield1, you have some terms mixed up I believe. The cassette you have is Hyperglide, not Uniglide:
Uniglide = twist-tooth, all teeth are the same. Slides onto freehub-body in any orientation, even inside-out to use unworn side of teeth
Hyperglide = flat-tooth with recessed shift-ramps on the side of the sprocket. Also has one wider tab on the inside that slides into the wider slot on the freehub (at 12 o'clock position on right cog).
Uniglide - left, Hyperglide - right
FH-7400 = 6-spd UG
FH-7401 = 6/7-spd UG
FH-7402 = 8-spd UG
FH-7403 = 8-spd UG/HG