[maxrpm]

I don't have a Bdr but I have had two shields crack. Billy Andrews at HRE Motors says this is fairly common and has more to do with the shield getting its strength from the glass itself, not the weak brass framing. Once I saw the frame without glass I realized how flimsy it really is. After the second shield cracked he replaced it with a polycarbonate that has zero distortion and looks like real glass. 4 years of crack-free racing/street driving. No one even questions it during the yearly state inspections.
Just my solution.