I am a newbie here but have some experience in this area. I have been riding since 1957 and have had my share of road rash.
To be specific, in this thread I saw the mention of 'roll bars' -some call them engine guards. In '92 my wife and I were at a stop sign when a drunk guy came off the road and tagged us real good. The left roll bar deflected the van, or move the bike back, just enough that the sliders took the full impact, scattering them both taking the front end off the bike. The roll bar was stright back and about an inch off the side case. The steel mount was broken like it was peanut butter. (Took 11 stiches to close my leg and three in my elbow.) The bike ended up 44 feet from the impaact site. I called Harley the next morning and asked how fast he had to be going, given the weight of a Dodge van. First they told me how lucky I was to be alive -which I for sure understood- and then said he had to be doing 52+ MPH.
Do I beleive in roll bars? Yes I do.
In fact, we rebuilt that bike (yes the frame was strightened) and I am now going through it again. I have seven gallons tanks going on and had to find a extra wide roll bar.
Roll bars, don't leave home without them.