Converting my old Soul to a commuter / occasional hardtail. Previously had a double and bash (Prior to that had a 44t big ring) and I want to put as big a ring on it as possible/practical. I’ve got a long rear mech and an old XT front mech.

How do I tell what i can get away with?

I used to run an rigid mtb as a commuter and fitted a 48t ring that was fine paired to 32/12 at the back I was using an stx rc ( it was a while back) front mech. I was told at the time that the lower end mechs were better for larger rings as higher end one run to finer tolerances , could be a load of bull but it worked fine. If you wanted to use a bigger ring maybe have a look at fitting a road triple front mech.

You can get 48t 104bcd outers.Might have to lift the front mech a little more than ideal (curve of the fd cage will be too tight) and the shifting might be a bit haphazard if you’ve got a 32t middle.
But I’ve made it work on quite a few peoples bikes who were doing the same.

Hmmm. Might check out a 48t then. That could be ideal

My TT bike runs 650c wheels and that has a 55T big ring. Im sure that although the wheels are a similar size i wud hate that ring on an mtb.

my daughter rides an old HT with Michelin 1.25 slicks and she can spin that out with 44×11