Fork end#Derailleur hanger

A hanger is the connection of the bicycle frame to the rear derailleur. The function of the eye diagram is (e.g. by reprecipitation or falls) to protect the bicycle frame in the case of collisions to the rear derailleur from damage by bending. Instead, bend or break the hanger as simple and inexpensive to be replaced component.

The derailleur hanger is usually mounted on the rear right dropout with one to three screws and also clamped supportive even with the quick release of the rear wheel. It has an internal thread into which you can screw the mounting bolt of the derailleur. In older or cheap bikes you can not change the hanger, it is an integral part of the frame. But even in high quality frame, it may happen that no replaceable derailleur hanger is available. Due to the escalating variety of models, it always comes back to procurement difficulties at the moment of switching. In IGH no derailleur hanger is needed.