Originally Posted by Mig1NC
Has anybody figured out the exact distance from the bottom of the racquet yields the highest gain in MgR/I for the smallest increase in static weight?
Maybe many great racquets have the same MgR/I (e.g. 21), but the reverse is not true.
Very few racquets with MgR/I = 21 are great. So as a design criterion for customizing racquets it is a very dangerous concept and would avoid it if I were you!
If you still want to find the minimum added weight m you can use:
m = (M*R-c*J)/r(cr-1)
Where M, R and J are the values for the original racquet. m and r are for the added weight and c = 21/g (or what ever value you are striving for).
You can find the r that gives you the minimum m by taking the derivative dm/dr = 0.
But that leads to a fourth order equation, so it is not so fun. It is probably easier to plot the equation in Excel and see where min lies.
You can also see from the equation that you should avoid r=1/c (46.7 cm) since that will require an infinite weight to achieve the right value.
racquet apps for the iPhone/iPad.