Shimano’s M6100 Deore is the big news today from the component manufacturer, but alongside the release of this value-packed 12-speed group are additions to 10- and 11-speed mountain bike drivetrains that will allow riders to expand the range of their existing drivetrains with minimal investment. Here’s a rundown of the stand out parts as well as component compatibility between them.
What’s the difference between Deore M6100, M5100 and M4100?
Shimano’s M6100 is an entirely new group that features many of the same technologies and component standards as XTR, XT and SLX. It is a dedicated 1×12 group with a 10-51t cassette that requires Shimano’s Micro Spline freehub body.
In contrast, the 11-speed M5100 and 10-speed M4100 lines of components aren’t complete groupsets, but rather, a series of components intended to update existing drivetrains. They will also offer more gearing options for entry-level mountain bikes in the coming years.
Think of M5100 and M4100 has hardware updates for your bike.
Shimano M6100, M5100, M4100 Component Compatibility
Shimano Deore M5100
Shimano’s Deore M5100 line includes new shifters, redesigned 11-speed rear derailleur and a new 11-51t cassette that is compatible with Shimano’s longstanding HG freehub body. Riders who prefer doubles can benefit from the new, wider-range 11-42t cassette.
The FC-M5100 crankset is compatible with single or double chainring 10 and 11-speed drivetrains. The 1x version is offered with 30 and 32t chainrings, while the double comes with 36/22t chainrings.
This group also sees the addition of I-SPEC EV to the components in order to create a better-integrated cockpit with the company’s higher-end components.
Shimano Deore M4100
Where the M5100 line address updates to 11-speed drivetrains, the M4100 group serves to update 10-speed systems with a new shifter, cassette and derailleur options.
The 11-46t cassette makes 1×10 speed systems more reasonable for many riders. As with the 11-speed updates, Shimano is offering a 10speed cassette with a wider, 11-42t range for 2x drivetrains.
As with M5100, this group also sees the addition of I-SPEC EV to the components in order to create a better-integrated cockpit.
Compatibility between M5100 and M4100
As mentioned above, the FC-M5100 crankset is compatible with both 10 and 11-speed drivetrains.
In addition to having a dedicated 1×11 rear derailleur in the M5100 line, Shimano has also added the RD-M5120 model which is compatible with both 10 and 11-speed systems for use with 1x and 2x drivetrains (with a maximum cog size of 46t.) This new derailleur features Shimano’s Shadow RD+ system which a clutch mechanism to maintain tension on the chain in order to improve chain retention and shift performance.
Below this derailleur is the RD-M4120. This model is also compatible with 10 and 11-speed systems but lacks the Shimano’s chain retention technology. We recommend sticking with the model up for serious riding.