I am assuming yes, but sometimes assumption can lead to a complete **** up!

Currently have a 105 rear mech but will need a mech that can accommodate a 11-32T rear cassette and the 105 is rated to only 28T.

Thank you!

Not tried it but was told before you can’t mix the shimano road/MTB stuff.

bollops.

that’s pants!

If it’s a 9spd XTR mech, then you’ll be fine.

Problems with mixing road and MTB Shimano kit only occurred when 10spd MTB stuff came about and had a different cable pull ratio.

Shimano: A 10-speed 105 shifter will work with a 9-speed MTB mech on a 10-speed MTB cassette

bonkers but thank you!

Oh, and a 5700 105 short cage mech is fine up to 30T cogs on the back, and a medium cage 105 mech will handle up to a 32T, so you don’t need to go to an MTB mech if you don’t mind buying a new one.

*head spins!*

Cool – will look to swop out for a medium cage.

Thank you!

Wot drewy scotroutes said – 9sp mechs work just fine with STIs up to at least 10sp, but mboy’s advice may mean it’s irrelevant for you.

Yes I have an old-ish set 9sp 105 flght levers and have used 9sp XTR rear mech, as you say to get a larger cassette for Pyrennes duties when touring, so yes it can work. Actually my XTR is still on the bike as it works:)