bikeworkshop
Senior Retro Guru
100mm should be ok.
So if you've got a 27.2 post, and your 31.6 post is sloppy, I'd suggest you get a use shim with wall thickness of 2.3mm (so diameter difference post/ tube is 4.6mm), and then slim it down to size if required - you can mount it in a drill.
So if you've got a 27.2 post, and your 31.6 post is sloppy, I'd suggest you get a use shim with wall thickness of 2.3mm (so diameter difference post/ tube is 4.6mm), and then slim it down to size if required - you can mount it in a drill.