Yes (I believe) - although I've not tested it .
Yes it does look like you are correct on this Jupestar. The way Shimano get round the fact the two cassettes are different lengths is to include a spacer with the 11-34. So going back to the OPs post where he suggests buying a CS-HG700-11 cassette - this should come with the spacer..which he can then LEAVE OFF to make the cassette compatible with a narrower MTB hub spline. Someone like me with a Mavic 11 speed road hub on my road bike would leave the spacer on.Jupestar wrote: ↑24 Nov 2022, 9:09pmYes (I believe) - although I've not tested it .
I believe the 34t cog will be tapered so it sits further inboard, as it sits higher the spokes are further away than at the 28t cog height so it can afford the space to taper.
Hence why the 34t cassette would have a narrower spline fit, but with the same spacing and cog width, and therefore need a spacer on the road Freehub.
Again not tested...
I have not yet tried it myself, but having read Brucey's various posts about shortening cassettes, I think it should be possible to fit an 11 speed cassette with 32t or smaller largest sprocket on an 8/9/10 speed freehub by removing the 1st and 2nd position sprockets (11t and 12t respectively), and fitting in their place a 1st position 12t sprocket*, together with a corresponding larger lockring and thin washer designed for a 1st position sprocket of 12t or more, plus whatever thickness of washer(s) might be needed given that the removal of one sprocket will reduce the cassette width by more than the ~2mm difference between 10 and 11 speed road freehubs. I presume the larger lockring and thin washer would not necessarily need to be those made specifically for 11 speed cassettes.