There is a new part for stabilizing the rear derailleurs of Shimano and SRAM:
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Stiffshifter
Stiffshifter – Stiffening for the UDH derailleur hanger The Eightpins Stiffshifter is the next evolutionary step for bikes with UDH derailleur hangers. Modern derailleurs are longer, wider, and more exposed than ever before – and the UDH derailleur hanger is simply too weak for this. Even slight...