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I have a Dura Ace 8-speed uniglide rear hub/freewheel marked 'Integrated 8 SIS' and an 8 speed uniglide 14-21T cassette.

Two issues - the first being that the smallest cog needs to be a special 32mm Dura Ace thread, I think this issue unrelated but include the info in case it is. (32mm 14T Dura Ace cog on its way)

The actual issue I'd like to clarify appears to be the size of either the cassette or the freewheel on the hub is incorrect.

If I stack 8 speeds I run out of splines and the second to smallest cog (15T) would just spin if I were to apply torque:

enter image description here

If I try 7 speeds, I cant thread on the smallest cog as it'll hit the splines:

enter image description here

If I add a spacer to the 7 then it appears to all fit. But it's hardly correct, this is meant to be an 8 speed system right?? :

enter image description here

Measuring the pitch I see that it is indeed 8-speed (4.8mm), yet the stack height appears slightly larger at 35.85mm (it should be 35.4mm) - probably due to the smallest cog and the black spacer (0.3mm thicker than the others).

enter image description here

The only way I can see to maybe get it working would be to turn off some of the uniglide splines on a lathe and use two Dura Ace threaded cogs (14T and 15T) - the 15T one wouldn't have as much thread to work on in this case. Or perhaps running pins through the 3 holes that run through the cogs and spacers?? I am yet to check if doing that would leave enough room between the smallest cog with chain on and the frame..

Edit: Another option is buying another 32mm threaded Dura Ace cog in 15T and turn/file/mill out the uniglide teeth on it for use as the second smallest cog (14T would be another 32mm threaded Dura Ace cog)

Hopefully this is something basic I'm overlooking? ;)

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    That is an awesomely well documented question! And superbly clean gears to boot. Excellent first question. – Criggie Jan 22 '18 at 6:44
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    Possible helpful info: hub model number stamped on shell, measured over-locknut dimension, and whether it's possible this hub might have had a freehub body transplant at some point. – Nathan Knutson Jan 22 '18 at 7:58
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    @NathanKnutson, Thanks for your interest. No model number I can see, however I suspect it's 7402. Not sure what the 'over-locknut dimension' is, but the threaded section on the freehub is 31.9mm OD (Dura Ace 32mm) - where the cog goes and locks the rest in yeah? Dropout to dropout is 130mm. Can't tell if the freehub has been removed. :) – Lamar Latrell Jan 22 '18 at 8:05
  • +1 for providing plenty of info and pics and the use of MS Paint :-) – Argenti Apparatus Jan 22 '18 at 13:23
  • Over locknut is the 130mm. If the hub had had a freehub transplant to 6 or 7 speed I don't think it would still be able to come out 130 exactly unless spacers were added, which would be obvious, so that probably eliminates that possibility. – Nathan Knutson Jan 22 '18 at 17:27
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This is not my area of expertise, but at first glance you have a 6/7 speed freehub body, not an 8 speed as you thought.

I see the threads on the 8 speed are cut into the splines, whereas yours has a continuous thread all the way around, but its lower than the highest part of the splines.

Some photos thanks to google images:

enter image description here

enter image description here

Images from https://www.bikeforums.net/classic-vintage/626072-dura-ace-freehub-id-7400-7402-7403-101-a.html and theres more info there.

  • Thanks for your input, however - unless I'm mistaken (?) - this doesn't explain why 7 speeds wont fit without an extra spacer? – Lamar Latrell Jan 22 '18 at 6:58
  • @LamarLatrell you got me there - I have no idea, sorry. – Criggie Jan 22 '18 at 7:01
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Excuse the self answer but I have learned that my hub is a special 7402 hub that came out during the phase out of uniglide (around '88 to '89), it has an equally special and unique cassette requirement where the second cog in doesn't use a plastic spacer as my cassette does.

I am yet to see one so it's hard to describe what I can only imagine..

Anyways, I can either:

  • Wait until one of these turns up on ebay and in the meanwhiles ride 7 speed. (I'd drive the rear derailleur end stop riiight in to stop me pulling the chain on to the spokes)
  • File/mill/broach out a Dura Ace 32mm 15T threaded cog to fit the splines (maybe have to TIG weld in some extra material for this), then fit a standard Dura Ace 32mm threaded 14T on the outside.
  • Put the hub in a lathe (via the offside flange with a live (or even dead) centre in the drive side quick release bore), then turn off 3mm worth of splines and increase the threaded section so that I can use a Dura Ace 32mm 15T threaded cog and a Dura Ace 32mm 14T threaded cog together.
  • Buy an expensive and special 7402 freehub removal tool, bin the freehub (and the tool which is now useless to me :), and install a hyperglide freehub and cassette.

I just wanna ride - 7 speed it is.

🚴🏿🙃

  • Great work - you should mark this as the accepted answer because its what works for you. Another option is to flog off the whole thing on ebay and buy something more accessible. I have a steel 80s road bike with 9 speed rear, it works. – Criggie Jan 23 '18 at 7:50

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