11 speed shimano rear derailleur compatibility with 12 speed cassetes and shifters.

[lucas-mior]

I currently have a shimano 11 speed rear derailleur, shifter and cassete (group deore 5100). However, I am planning to switch to a 12 speed cassete compatible with HG free hubs (shimano does not make those but other manufactures do). From research I have done, the rear derailleur of shimano 11 speed (5100) and 12 speed (6100) seem to be interchangeable. Have you any experience with that? And what about the shifter? Should any 12 speed shifter work or are they different?

 

[BikeGremlin]

I currently have a shimano 11 speed rear derailleur, shifter and cassete (group deore 5100). However, I am planning to switch to a 12 speed cassete compatible with HG free hubs (shimano does not make those but other manufactures do). From research I have done, the rear derailleur of shimano 11 speed (5100) and 12 speed (6100) seem to be interchangeable. Have you any experience with that? And what about the shifter? Should any 12 speed shifter work or are they different?

Briefly: I'm not sure.

In more detail:

Digression:
I don't see much point in moving from 11 speeds to 12 speeds on a functioning bicycle.
I also don't see the need of using indexed shifting (instead of friction shifters), but that's a different matter/topic.

I haven't got any at hand to measure.
If the same RD is used, and the same shifter, then the question boils down to whether cassttes have the same spacing (because that is the only way they could work if the other two factors remain the same).

Shimano XTR 9100 shifters have a switch to go from 11 to 12-speed mode, but that works with Shimano XTR 11 or 12-speed microspline cassettes. I am not sure about the 12-speed HG spacing (or 11-speed HG spacing for that matter - does it differ from microspline spacing).

Relja

 

[lucas-mior]

I will convert to 12 speeds only when my cassete wears out. I don't like friction shifters.

I know that I will have to change the shifter, because shimano 11 speed shifter will not work on 12 speed cassetes. My concern is what 12 speed shifter works with 12 speed cassetes on the wild. Assuming the RD is compatible with 12 speed, can I spec cassete and shifter accordingly to one another? Or does the RD imply one type of cassete and/or shifter?

For now, I will try to gather info about the spacing on cassetes made for HG free hubs.

 

[BikeGremlin]

I will convert to 12 speeds only when my cassete wears out. I don't like friction shifters.

I know that I will have to change the shifter, because shimano 11 speed shifter will not work on 12 speed cassetes. My concern is what 12 speed shifter works with 12 speed cassetes on the wild. Assuming the RD is compatible with 12 speed, can I spec cassete and shifter accordingly to one another? Or does the RD imply one type of cassete and/or shifter?

For now, I will try to gather info about the spacing on cassetes made for HG free hubs.

I wrote this article exactly for situations like this:

https://bike.bikegremlin.com/1212/compatibility-what-combines-with-what/

It explains the key concepts you need to understand before attempting mix-matching (or drivetrain swaps in general for that matter).

Once you grasp the basics, you’ll know what to look for when checking whether a shifter, derailleur, and cassette can work together.