more than likely yes. if you've ever heard of the 400cc craze of the late 80's early 90's then its because in japan you have to pass a test to ride a limited 400cc bike then another far more expensive one for anything bigger, hence the 400cc market. in the uk we've just got the kawasaki 250R superbike and i use 'superbike' loosly as its only got 33bhp to coincide with our laws over here
try looking on kawasaki.jp for more answers, well, that said you might need to run the site through a translator first!