Shimano heard you like options, so they’re bringing the full spread for the newest Deore generation. In addition to the premium level Deore M6100 12 speed group, Shimano is also adding 1x and 2x groups in both 10 speed and 11 speed versions. Importantly, none of these options require a Micro Spline freehub in spite of offering wide range 1x cassettes, making Shimano 1x drivetrains more affordable than ever.
Split between the 11 speed Deore M5100 group and the 10 speed Deore M4100 group, there are four different build combinations – though there are a few parts that are shared between the different configurations.
At the crankset, both the M4100 and M5100 groups use the same FC-M5100 10/11 speed crankset. These use a 52mm chainline and 30 and 32t single chainrings, or 22-36t 2x chainrings. Compatible with both 10 and 11 speed drivetrains, the cranks will also work with 135 and 142mm QR spaced frames and 142 an 148mm spaced thru axle frames.
There are four different cassettes offered, two each for 10 & 11 speed. The 5100 11 speed cassettes come in 11-42t Rhythm Step for 1×11 or 2×11, and a true wide range 11-51t for 1x only.
The 10 speed 4100 cassettes are offered in 11-42 Rhythm Step for 1×10 or 2×10, and an 11-46t wide range cassette for 1×10. Note that all of these use the standard Shimano HG freehub body for wide compatibility – but that’s the reason for the loss of the 10t cassette and extra gears.
Only the M5100 1 x 11 group will need a specific derailleur – the RD-M5100. This allows for up to a 51t maximum cog and offers clutched Shadow RD+ tech you’ll find on more expensive derailleurs.
Then there are two separate 10/11 speed rear derailleurs in the RD-M5120 and RD-M4120. The 5120 offers Shadow RD+ tech, while the 4120 uses standard Shadow tech (no clutch). The 5120 also clears up to a 46t maximum cog, compared to the 4120 which will only clear a 42t. Both derailleurs will work with 10 or 11 speed drivetrains, so you can choose the derailleur based on the maximum tooth size you’ll need.
Since the front derailleur is not dead with these two groups, new FD-M5100 and FD-M4100 front derailleurs will be offered in various frame fitments. Note that the cage width is different for 10 & 11 speed so you’ll need the proper front derailleur.
Both 5100 and 4100 groups also use existing 10 and 11 speed chains.
And of course there are a bunch of different shifter options for 1x and 2x, with and without the shift indicator pods, and band clamp or I-SPEC EV.
Finally, a new BL-M4100 non-series brake lever has been introduced that will pair with existing calipers. Add it to the BR-MT410 2 piston caliper to make the updated MT410 brake, or the BR-MT420 4 piston caliper to make the MT420 brake. The lever features new architecture and is I-SPEC EV compatible.
Confused about all the different options? Don’t worry, it’s a lot. Fortunately, Shimano put together this handy flow chart to help make sense of it all. If the part numbers are connected with a dotted white line, they’re inter-compatible. It also gives you an idea of what parts you’ll need to make a 1×12, 1×11, 2×11, 1×10 or 2×10 drivetrain.
Shimano Deore M5100 and M4100 components will be available in the following weeks, with pricing TBA.