hello , steve
in truth its very much like the k3 .the tank on mine is the maroon that we saw on the f2 with the same style striping decals as the k3 but in different colours to match ie blue with gold pinstriping the side panels have different 550 badges and are topped off with chased gold pinstriping and a a bold letter K.. very nice ,,,,,,, the seat has more of a rear hump and for my money is the most comfotable of any of the k,s or f,s along with usa switch gear ie lights on all the time thats about it as iam better with a spanner than this computer photos to follow when my kids get home from school ...
if your interested over the last 16 years ive owned 2 f1 s 1 f2 and this k4 and it shares my life with a cz250 , p50 , c90 , pf50 and more projects than i care to mention plus miner details like ball and chain kids cars etc etc ..... Garry