in some "x-treem" instances where you guys a really doing some knee dragging the spools may not be the best thing for you. as for extrusion with the railz the average is right round an inch on the bar and another inch for the slider. it varies per bike. but rickys pictures at the beginning of this post give a great reference point.

by the way the blue for the 750 is a near perfect match and i have them in stock if you want to come by and take a look at them.