CV or not to CV

[Gene]

I've got a stock '85 650sc Nighthawk.


it has CV carbs, I wonder why?


From what I've heard elsewhere, it's to help pass smog. Is this true? if so, how.


I know once I dialed the carbs in, the throttle response is almost instananeous, almost as good as a two-stroke.

[mollusc]

I can't answer the question of why, but don't all Nighthawks use CV carbs?  Along with almost all other Japanese bikes between the early 80s and mid 90s?