Shimano 12 speed derailleur with 11 speed cassette and shifter

[steverav1]

Looking at upgrading the derailleur on my e160 I have 11 speed drivetrain 11-51 cassette. The only derailleur I can find is the deore I have already got fitted. So I was wandering if a 12 speed xt or xtr derailleur can be used on a 11speed drivetrain. Cheers in advance

 

[steve_sordy]

No responses so far. I'll have a go.
I have never tried it, so take that into account.

The main problem could be whether the chain will roll through the jockies. I am pretty sure that 12-speed chain is narrower than 11-speed, but I have never measured it to find out.

The mech will move in the increments determined by the shifter, so that shouldn't be a problem.

 

[Snrbrtsn]

I use the set up on sons bike (11 Speed)
This was used to keep spare parts to minimum

Note - I have 12 speed xt on Levo
My sons bike, is not an EMTb, he runs single chain ring, 11 Speed cassette & shifter with 12 Speed chain & rear mech
Bit of a faff setting the limits but no issue shifting “or back pedalling“