I am in exploring this conversion now too. I'm done with SRAM brakes AND the thumb only shifters after a sketchy weekend at Dupont's beautiful Ridgeline trail.
Im converting from full couple month old SRAM XO/1/RS 11sp setup that I feel I gave a fair shake over the last couple months.
I am trying to utilize my older
flawless XTR 10sp + items. I say + because I have a full set of XTR M980 shifter/brakes. I would like to adapt / upgrade them by adding the M9000 11sp shifter to the M980 iSpecI brakes, but they now have iSpecII!
Q1: Has anyone bolted the iSpecI M980 adapter to the M9000 shifter and will it work?
Looks like that common bolt is very simmilar and should work? Anyone / thoughts?
Q2: Anyone have a M9000 to test they have laying around from maybe going from Shimano to SRAM? And possibly said matching derailleur?
The Duckster wrote on 05/11/17 at 8:22pm:
I pulled the trigger on the shifter upgrade today! I decided to go with the XT Derailleur and the XTR bar mount shifter!
Q3: @Duckster did you finish this and A: did you end up upgrading the derailleur as noted and B: how well did it work with SRAM cassette & chain?
BudLeach wrote on 05/03/17 at 5:45pm:
Only problem is you will also need Shimano derailleur since the cable pull ratio is different between SRAM and Shimano. Most will probably say you will also need a Shimano 11 speed cassette and chain as well if you want to go with Shimano shifting. I have seen a Shimano XTR shifter and derailleur work perfectly fine with a SRAM XX1 cassette and chain. I would say you will probably be just fine with your current cassette and chain with a shimano shifter/derailleur combo.
Q4: @BudLeach, or anyone else that has used / tested the M9000 shifter w/the XO derailleur to test / confirm the pull ratio is off enough to not work? (to minimize my cost of conversion and not having to throw a derailleur on top of it all)
Lastly for the sake of the other side of the coin debate of the thumb only shifting on top of index braking. I find taking both my thumb AND index finger off the grips on a gnarly decent minimizing how much hand I have wrapped around the bar is far less desirable then a wickedly fast index finger move. And if its that gnarly your probably pretty hard on the front brake too so your not going to far out of control. Just food for thought on the flip side and seems entirely a personal preference.