Derailleur hanger

A derailleur hanger comprising:

• a first portion configured to be mounted to a hub axle, ;
• and
• a second portion coupled to the first portion, and configured to support a derailleur,
• the first portion including a frame contact surface disposed in a reference plane extending perpendicular to a center axis of the hub axle in an installed state where the derailleur hanger is mounted to the hub axle,
• the first portion including an axle contact surface being configured to contact with a hub axle in the installed state,
• the second portion including a first surface disposed on a first side of the reference plane and a second surface disposed on a second side of the reference plane, the first side being opposite to the second side with respect to the reference plane, a vehicle center plane being positioned at the second side in the installed state,
• the axle contact surface being disposed on the second side of the reference plane, the axle contact surface being disposed farther from the reference plane than the second surface.