Join Date: Feb 2004
Location: Canton, Ohio, USA
motorcycle rotors aren't turned anyway. they are Blanchard ground. 2¢.
if they are actually warped (rarely the case), pitch them. or, use them as yard art.
they most likely have irregular pad material buildup. you can remove it with some elbow grease and various techniques as already laid out by others.
if they have hard spots (irregular blueish spots) it's back to yard art.
1991 851 SP3
1966 250 Monza
1999 Moster 900 City (not so much City anymore)
appearing to appear to know what I know.