yes, i have upgraded to bigger size tire 130 120. yeah, the piece of material is ON THE CASE. the shroud screw bolts to IT.. CLOSE ASS FIT ANYWAY. didnt do it untill i stretched out/back on my ride home.. the back left side, just a lil tit that sticks out so the left side shroud can screw tight... yeah, it put a groove AROUND WHOLE DAM TIRE...