Suzuki RG 500-The Racing Myth
"Suzuki RG 500-The Racing Myth 1974-1980" by Massimo Cuffiani is a wonderfully detail-packed look at the racing RG500 over that period.
Cuffiani is a huge fan of the RG500 and it shows in this book. He has also managed to achieve interviews with numerous RG500 racers. mechanics, and championship-winning riders. There are also a HUGE number of detailed photos of the various bikes, with fairings on and off, from all angles.
If you're a fan of the RG500, just get this book. It needs to be in your collection. For the price of a couple of pizzas, it's a bargain.