I'm friction shifting 9 out of 10 cogs on a bike with 126mm between the rear dropouts. It works very well for me. Some details....
I started with a 10 speed cassette with 11-12-13-14-15-17-19-21-24-28 cogs.
I broke down the cassette and reassembled with just the 12-13-14-15-17-19-21-24-28 loose cogs and the 10-speed spacers on a Shimano Exage FH-G50 hub.
The 9 cogs and 8 spacers do not "fill" the full width of the freehub, so I added a 1.6mm spacer between the 28 tooth (9th position) cog and the inboard flange of the freehub.
I'm using a 10-speed chain, 46-34 chainrings, and early 80's Campy Super Record RD & FD.
The setup provides a 32" to 101" gearing range and it works like a champ.
Dean
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