Alloy Freehub
 

Are there any alloy freehubs available to retrofit older Shimano DA and Ultegra ?

Thanks

Steel is a alloy.

But I guess instead of being a smart ass, I'll accept that people commonly refer to aluminum by the term alloy alone. Many freehub bodies are aluminum alloy. And you can also get titanium free hub bodies. Steel free hubs are probably a majority of the lower tier and less costly free hubs.

You could retro fit your old wheel with a entirely new hub of a better brand that will probably be aluminum or titanium. I'm sort of surprised your old DuraAce isn't one or the other. But I never had any of the mid or upper tier stuff when I was growing up BITD.

Which generation of older Dura Ace or Ultegra freehub are you looking to do this on?

I generally wouldn't want a aluminum freehub as those get chewed up quickly and easily. Titanium is the way to go if you can or steel if not. What hub do you need a freehub for?

If you mean aluminum, no, realistically only the DAs that originally had aluminum can use one. The method that is used to attach the freehub body to the hub shell is different. Pull up the EV doc from Shimano for the FH-78??. The wheelsets are similar for both DA & Ultegra in this era, (the shortened tall splined body).

The only other Shimano aluminum is probably the newest DA wheelset, which uses the new 'direct engagement' ratcheting system. There could be others that were part of wheelsets (WH-????).

Going with a titanium freehub body there are a few possibilities (if you can find a DA or XTR Ti body). Depending on the style, these could possibly be used on a freehub that originally had a steel body. IE: a freehub from the FH-7700 could possibly fit on a FH-6500 shell. The XTR bodies may also fit some hub shells.

Yeah, I was aware of all that. I thought that there might be some magic that I didn't know about.
Thanks

Yes, most of the older Shimano freehubs (except for the already mentioned 'shortened 10 speed' versions) have the ratchet & pawl in the freehub body. This design probably doesn't lend itself to having an aluminum outer body. Don't know of any aluminum body with this design and the Shimano shell/body attachment interface.

And even the Ti ones seems to have limited weight savings, probably since it still uses a steel inner body. Shimano list the FH-7700 (Ti) as being only 35 grams lighter than the FH-6500.

There are many generations of Dura Ace and Ultegra/600 hubs. Which generation specifically are you talking about? The FH7400 one cannot be updated with a different freehub body. The FH620X, on the other hand, might be- at least from the Shimano drawings it looks to have the same interface as later HG freehub bodies.

Yes, the mount interface is similar but depth/thickness of the freehub body needs to be similar, if not the freehub body will 'stick-out & add too much width to the drive side. This will cause poor dishing of the wheel.

The Shimano Ti bodies have a thicker 'rear' and require a hub shell that accepts that. The Ti bodies are similar to the 4400 below, or deeper for some XTRs. As mentioned earlier, 7700 Ti body may fit on a 6500 (which is similar to the 4400).

https://cimg1.ibsrv.net/gimg/bikefor...97afd8cac8.jpg

As noted earlier, the few Shimano aluminum bodies used a different mount type. Don't know if anyone else used the common Shimano body/shell interface (like the FH-62??), and if aluminum was ever done. Most of the aluminum bodies by other makers use pawls on the body & ratchet in the hub shell (similar to the FH-7800, which is a unique design for Shimano).