Size of the Roadster Outer Tube

U somehow managed to order the wrong Memphis shade kits and am calling tomorrow to debut I can trade out the clamps
 
yep....you fellas with your fancy callipers and squares were making it altogether too complicated....just wrap a piece of paper around the tube, mark the overlap point, unwrap and measure the length of paper to the mark, divide by Pi...done
Sooooooo old school