I could not find the old mud guard rubbing post to add this onto, but I tried a simple fix to prevent this problem on the XR650R. I bought a 1" wide thin strip of aluminum from Lowe's, cut it to length to wrap around the lower part of the mudguard (about 6" long I think), and pop-riveted it in 3 places about 2-3 inches above the bottom of the guard. This allows you to form the lower part of the plastic guard in pretty much any shape you want it. It seems to work pretty well so far!!