Ok my front Brake rotor on the right side is bent had the bike for month and just the past few days started hearin a grindin noise but not like bad brake pads cause it wasnt constant it would spin like half way then grind constantly, so i had a buddy ride it and watche it and ya my rotor is bent what would cause this?? brake pads are fairly new so the guys says that i bought the bike off of. Is it possible at all to bend them doin wheelies?? i really dont see anyway that could happen j/w though.