Topic starter
I've been looking at the possibility of extending the lower end of my gears on my GRX400 drivetrain by replacing the rear mech. with one with a higher total capacity and have been trying to fathom Shimano's cable pull ratios. Anyway, after plenty of searching I've come to the conclusion that I'm not going to get my GRX400 shifters (road 11 speed pull) to talk to a spare trekking mech (T6000) mech I have or one of the new, higher capacity CUES U6000 mechs (1:1). I suspect that I'll just have to stick a bigger cassette in and run it over capacity.
Anyway, on my intellectual travels I found an interesting website listing all the various Shimano cable pulls, so out of idle curiosity, is there any rationale to using a particular pull for a particular type or speed of drivetrain or is it as arbitrary as it seems?
Posted : 12/04/2025 5:18 pm
You can run Shimano 10 or 11 speed road shifter with and MTB mech by using a Shiftmate. I think Shiftmate 8 does 11 speed but probably need to look carefully through the charts and find the correct one.
https://www.jtekengineering.com/shiftmate/shiftmate-compatibility-charts-choices/
Posted : 12/04/2025 6:14 pm
Topic starter
Thanks for that, they're only a few miles away from me. However I'm not sure that there's an 11 speed road to 10 speed MTB option. I've dropped them an email to see if there can help.
Posted : 12/04/2025 6:37 pm
I ran a 10 speed zee mech with 11s road shifters and a wolftooth tanpan (edit- 1x10s mtb cassette). I wouldn’t have called it shop-perfect shifting but it was functional enough with clean cables that I used that setup for at least a couple of years.
If you’re buying adapters it would probably be easier to buy the GRX 11 speed rear mech designed specifically for mountain bike cassettes wouldn’t it?
Posted : 12/04/2025 7:19 pm
Rationale?
Introduced incompatability to generate more sales.
They will have an engineering rationale but i am cynical
Posted : 12/04/2025 11:26 pm
You could swap the chainring to a 38T, presuming the original is 40 or 42
Posted : 13/04/2025 1:26 am
GRX mechs are interchangeable between 11 and 12 speed.
Fit the 810 12 speed mech and run an 11 speed 11-51 desire cassette.
Posted : 13/04/2025 7:15 am
rOcKeTdOg reacted
