shroud

I wanted to put an R&G radiator guard on my 2017 RC 390; but the OEM radiator shroud needs to be removed to install it. What's the purpose of the radiator upper and lower shrouds? I was wondering if I can remove the shrouds to install the radiator guard and shed some weight.

I've been looking at the flexible rubber shroud between the radiator and engine head. At first I thought it was to improve cooling, but I'm thinking more that it might keep the hot air off the rider and maybe reduce engine noise. Do the Cup bikes have this floppy rubber sheet like the street...