I know that people have got the Zee rear mech working with range extenders so I’m pretty sure it’ll work with the 42 but will it work with the new XT M8000 11 speed rear shifter and cassette? ie 10 speed rear mech with 11 speed shifter to provide 1×11.

(going on a hardtail so no chain growth)

Anyone tried it?

I believe it won’t. i.e., an 11 speed cassette needs an 11 speed rear mech

In nature, it won’t cover the cassette. With an extension cage such as the OneUp it will cover the cassette.

The decider is going to be cable pull. The derailleur itself has no idea how many speeds it does, the clicks are measured by the shifter. If the cable pull works, then fine. If not, then no unless you start bodging washer stacks etc a la Shramano mashups.

People have definitely managed to get standard Zee FR mechs to work on 11-42 (10s). Chain length is fairly critical but that’s ok.

I understand of course that the mech isn’t a fixed number of speeds as such. The question essentially is “is a 10 speed Shimano mtb mech the same geometry as an 11 speed one so that it’ll move across the 11 sprockets correctly when using an 11 speed shifter”

The relevant numbers are all a bit different- link. I suppose it might be close enough to hack it together if you’re feeling optimistic…..

Thanks for that link – that was exactly what I was after. According to that Shimano mtb 10 and 11 speed rear mechs have different geometry (“Derailleur Ratio”) at 1.2 and 1.1 respectively but I note that the 1.1 figure is calculated and may not be exact – so basically it might actually be 1.2 but it may not…

Well, I ordered an 11 speed mech so what I’ll do is try out the 11 speed shifter with 11 speed cassette and the 10s Zee mech to see what happens in the real world.

Well I would have been able to tell you tonight. But for some reason evens sent my xtr 11 speed shifter and chain, which got delivered today, but left the xt m8000 cassette until today to despatch, despite showing in stock all the time!
Am planning on running with a 10 speed xt mech with one up rad cage to see how it goes

Cool. Well if it does work, I can always return the 11 speed mech…

(Zee on 42t)

So guys… Any news on the 10s rear mech on 11s trigger and cassette?

I’ve had the same idea btw.