I had a big interest in this bike back in the 80's. Having all but forgotten about it, I rediscovered it this morning. There isn't much out there. I found one photo that is fairly representative. I have a big color brochure floating around somewhere with the specs. It's pretty impressive. Anyways, if you're interested, there are some links here.
http://www.rotaryownersclub.co.uk/membersphotographs.htmHere's some specs-
http://www.diseno-art.com/encyclopedia/vehicles/road/bikes/rare_classic_bikes/norton_nrs588.html