In the instance that you wish to upgrade from the 11-42 system to the larger SunRace MX8 11-46 cassette and you already have the 11-speed derailleur installed, it should work with your existing configuration. However, you may be required to shift the B-screw slightly to fit the larger 46-tooth gear. This shift enables the right amount of clearance and desirable shifting capability. The cassette is, of course, compatible with both SRAM and Shimano 11-speed derailleurs.