Re: Hmm....
Not being anal enough to catagorize everything I see, I'd say a sportbike or race rep would be a...ummm.... replica of a race bike, IE forward crouch riding positin, low bars, high rearset pegs, tight fairing and instument cluster, cutting edge materials and technology..
a standard would be a basic motorcycle, IE upright riding position, higher handle bars, mid mounted pegs...still a technologically advanced engine and frame design but not the latest unobtainium..
A cruiser would be a flagrant Japanese attempt at buying into and copying a heritage they themselves do not posess. mainly because the market for heritage type Japanese motorcycles such as 90 cc step throughs.... chromed tank panels, pressed steel framed 160's and 125cc air-cooled two stroke twins is a little soft at this point in the US.
a Touring bike would be any bike with a large fairing and windshield, hard bags and possibly a trunk, upright riding position and gooshy seat. Most have some sort of gadgetry like cruise control, CD players and the like.
That leaves Harley, BMW, Triumph, Moto Guzzi and MV-Augusta which build pretty much what they've alway built, IE distinct motorcycles with a recognizable style they created themselves and have improved and tweaked over the years.
Customs, which I consider anything from choppers to bobbers to cafe` racers...ideally a stock platform modified by the owner into a more personalized version. But often now-a-days bought pre-assembled from small job shop type builders
And, Duel Sports which are usually standards with longer suspension and larger tanks for highway and mild off-roading.....
I think that pretty well covers it from personal perspective over the last 40 years as a motorcyclist..