When developing new SRAM drivetrain and Transmission products, we perform extensive system testing with the derailleurs, chain, cassette, and crank, to ensure high performance shifting. If the bike is setup correctly, and all components are within specification (including the wheels and frame), then individual cog derailleur adjustment should not be necessary.
If you are experiencing issues with shifting, chain rasp, or inability to shift into the large or small cog, it is most likely due to an underlying issue. Some things to consider include:
- Is the derailleur hanger bent? With 12 cogs on modern cassettes, it's important to use a quality hanger alignment tool to confirm that the hanger is aligned to your wheel, a visual check is not enough in most cases. If you don't have this tool, your local shop can check this out for you pretty quickly!
- Is the Chain Gap set correctly? (for non Full Mount/Hangerless models) See our manuals for instructions for AXS road and Eagle AXS MTB rear derailleurs.
- Are any drivetrain components worn or damaged and needing replacement such as chain, cassette, or chainrings? See our list of approved chain tools here.
- Is the chain length correct? See our AXS Road or Eagle AXS MTB manuals for information on the correct chain sizing process for drivetrains that use a standard derailleur hanger. For Full Mount derailleurs, please visit the Full Mount Chain Length Guide.
- Are you using a complete SRAM system (chain, derailleurs, cassette, chainrings)? SRAM systems are designed and tested to work together. Introducing a 3rd party component, like a cassette or chain may impact system performance. Additionally, using incompatible SRAM components (such as an 11-speed chainring and a 12-speed chain), will also lead to issues.
- Do you have a full-suspension bike? Did you correctly size the chain on the ground in the sag position? If no, please be sure to size your chain in sag. If yes, the chain might rasp when in a repair stand.
- Do you frame and wheel meet SRAM's frame fit specifications? If you switched from an HG or MicroSpline driver body to XD/XDR, it's quite likely that the new driver body will require a compatible end cap as well. Please check with your wheel or hub manufacturer if you aren't sure.
If you are confident that your rear derailleur trim issue is not caused by one of the seven conditions listed above, please reach out to our Rider Support Team or contact your local bike shop for assistance.