Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
There was no K2 in UK dont know about Italy.Engine numbers were consecutive so what apears as K2 in US is a K1 in UK up to 77 when 550 K3 came in.There were no differences in engines anyway
Italy definitely had the CB500K2-ED. Simplest way to identify a K2-ED, F, G frame is the central grease zerk under the swing arm. Is this page http://www.honda4fun.com/home/faq/generali/111-cb500-differenze-k0-k1-k2 useful? (scroll down). Up to engine number 2170314 the engine had the 8 rocker arm shafts. From engine number 2170315 it had 4.
I saw 500K registered in 76/77Graham but probably held over stock, if you put the frame/engine numbers of the UK 500 into the US number list the numbers say they are all earlier.From the numbers arround it seems that Hond were building 500 K1, 500K2 and 550K0 all at the same time