What a funny thread. And the guy wondering about diesel... hah?
You haven't even chosen a bike yet are thinking of getting a big one- with too much power- and restricting it down?!?
Then to top it off, people are talking about restrictor plates ahead of the carburetor, like that's even an option?
You do know that restricting AHEAD of the carb acts just like a.... ready?.... a CHOKE PLATE. If you restrict ahead of the carb the vacuum will pull more fuel; that's how the choke works.
Now if one is still thinking of restrictor plates and has heard of them in racing, those restrictors are AFTER the carb; between carb and intake manifold.
Still, it seems to me yet another case of trying to make a pickup truck into a sports car, and then taking a sports car and trying to make it into a pickup truck. Just get the small bike if that is the most appropriate choice.