I am new for MBT and want to learn something about repair/maintenance. I bought a Cannondale F400 from a guy. When I remove the rear wheel, I found some wear mark on the cassette side of the frame where the wheel is locked. Please refer the attached picture for detail. As you can see even the derailleur hanger is weared off a little bit.
My question is if such damage has any impact on the performance or safety and how to fix it.
I tried to find a new derailler hanger on amazon, nut I am not sure about the modle. Do you think the on in the following link is the same?
Thanks for your help!