Yeah, that's the locknut. I have loosened the locknut before, with a big punch or dull chisel and a hammer, but it will damage the locknut. You can make a socket to take the locknut off. You just need an old 1 inch impact socket and a grinder. Grind the end of the socket to form 4 equally sized tabs that fit into the locknut’s notches. Making this socket works a lot better than the punch and hammer, plus when you put the locknut back on, it needs to be torqued or it will probably loosen back up. Below is a picture of a homemade locknut socket.okay so i have the socket now. i read in the book that i am supposed to use the "honda special tool" to remove the locknut. surely i dont really have to have this tool do i?? and is the locknut the 4 or however many little edges sticking out around the allen bolt??