Changing roller size.

[A440A@AOL.COM]

 (I know bait when I see it):
JIM trolls, 

<< 'Some' areas a smaller knuckle would affect are:
Key dip, aftertouch, jack escapment, capstan height, backchecking and 
repetition speed. I am sure there are more but....................
 
       Ok,  Here we go.  I would like to hear the relationship between 
knuckle size and backchecking defined. 
Thanks, 
Ed Foote