Hey my front rotor sometimes scrapes along the left,well side part that moves to grip the rotor, and when I go pretty fast it makes the ringing noise like on a little kids bike horn maker thing, and makes me seem like a loser if any one hears it lol. What should i do?? Ive tried unpulling the knob at the end of that bar that connects to the bottom fork thing ( sorry I don't know all the technical terms) and twisting the other end circle screw at a different configuration to where the rotor moves away a little from the scraping side. It sort of worked lol. so ne other ideas??

ps-what are some good brand who make steel chainrings lol?