Currently running a 9 spd SLX Double groupset, and moving it onto a bike which requires a direct mount front mech.

I can’t seem to find an equivalent 9 speed double front mech? (only triple)

Will a 10 speed double front mech work, or will it do funny things with my 2 x 9 SLX shifter? (I thought the pull ratio was different on 10spd?)

Or am I best to buy a triple and limit the movement?

I’m interested in this, too.

A triple should work and, I think, a 10-speed mech, should work too but I’ve not tried it.

As far as I know a triple 9 speed mech will work fine

I think the triples will probably work too, but end up sitting very high above the crankset (due to the absence of a big ring).

Does anyone know if the 10 speed doubles will work with a 9 speed double shifter? (on 9 speed SLX double cranks). I’ve got a nagging feeling that it won’t…

Sheldon Brown

As far as I know the movement of the cage on the front mech should be the same on both speeds, so a 10 speed double should work, even with 9 speed shifters. It’s only dynasis rear that doesn’t work with 9s. . DM mechs have sliding mounts to give you better fit between 36, 38 and 40 T big rings, so as long as your outer chainring is that sort of size you should be OK. You may well have a good deal of patient trimming and tensioning to do, but I can’t see why it shouldn’t work. I think a triple would be a bit of a nightmare personally.

Shimano M665e is what you want, there’s one on pinkbike at the moment.
http://www.pinkbike.com/buysell/1440331/

I ran with a triple mech for a while, worked fine just looked a bit funny with the gap. Certainly better shifting with the double specific but the triple was ok.