I have a “freeride” Zee rear mech which has max (according to Shimano) rear cog size of 36T.

Has anyone used this rear mech with a 40T expander cog like the Hope or Superstar one?

If so, how was the shifting?

Yes i run one on my hardtail, shifts like a dream! T-rex 40t rear, Zee Freeride Mech 32t N/W front ring!

Yeah, same as russyh. Shifts fine, but that’s on an HT. Could be very different on an FS.

It’ll be going on my Krampus, 29+ with 30Tx36T lowest gear is fine for a couple of hours but I think on a big day out it might be “challenging”.

Looking into this as well but toying with the idea of the RADr cage with SS 40T ring, also on Zee FR mech.

Works well on mine, did need a longer B-screw though (came with the T-Rex).

I run a 30T front too, but 26er so a bit easier on the legs – not sure I’d fancy a 29er with the same gearing around here, especially on the long natural climbs (Scottish Borders).

For the record, i will be running the same set-up on my F/S when i finish building it, however with an XT rear mech as i believe it pushing my luck with chain growth. So for me Hardtail its spot on FS i wouldn’t chance it

Only lasted 1 ride for me. This was down to it being on a FS single pivot 29er, with a long chainstay. As such, chain-growth is significant. My medium cage XT lasted 3 months before being pulled inside-out, so I’ve decided that the 40t ring is too much of a bodge for this particular frame.

Fine on my Trance X 26er, but I did move to a RADr cage which works even better. 32NW up front, 11-40 (T-Rex) at the back. The RADr cage is worth it as it alters the geometry so that running on the extender cog is less of a strain and within normal B screw limits.