Hello , i fly ( 7 , 9 and 11m ) fuel with same size bar 17'' with 20 meter lines for 7 and 9 and 23 meter for 11m. From my point of view the 9m or 7m 2011 mode fly better in 20 meter lines. For the knots, i put both front and rear on middle knot in all the kite sizes. Just practice and see what is b...