I would like to remove the wheel that is being held in by this contraption:
I tried to use a standard socket wrench, but couldn't get just the right size: 1/2" or 13mm seems too small; 5/8" or 14mm seems too big.
Also, I'm not sure if there's a trick involving the black part. What's that called? Is there a special technique? The other end of the rod looks the same.