Originally Posted by
DannoXYZ
I think you only run into the issue where the freehub body rubs on the spokes when mixing 9/10-spd speed parts between road & MTB groups. The 10-spd cog-carrier that holds the largest cogs actually hangs over the end of the freehub body to move the largest cog closer to the spokes to gain extra space for the wider stack. This causes issues when retro-fitted to some older 9-spd parts.
For 7-spd, all Shimano freehubs bodies with 10mm fixing-bolt will work with all Shimano hubs. I won't mention anything about 7-spd DA or previous generation AX parts...
Hiya, Danno!
Nope. This was with relatively generic 8/9 speed cassette bodies on an older Deore XT shell (possibly M732 era). The hub shell had a little recess that covered the end of the cassette body. The "correct" MTB cassette body is built to space the cassette away from the spokes. If you put a "road" cassette body on it, everything fits but the big cog is too close to the spokes- the derailleur touches them.
I found this out while on tour a while back- the cassette body failed (sheared at the bearing cup) and the replacement worked fine, until I shifted to the big cog. Then the derailleur went ting-ting-ting on the spokes. Frustrating. I ended up replacing the whole hub with an Ultegra.