Basically what Psycho told you is not true.All carbs need a vacuum to operate. It has something to do with physics, oh yeah, the venturi effect. That drawsw the fuel out of the float bowl, through the jets and into the carb venturi(clever name)where it atomizes and mixes with the air.
CV carbs operate on a pressure differential between both sides of the slide diaphram. The only effect the airbox has is to provide one side of that differential. If you are running pods you will need to rejet.Power is based on airflow through the carb and the CVs have an extra butterfly that does restrict airflow compared to a non-cv of the same bore diameter. As far as throttle response goes a properly set up CV is virtually identical to a non-cv except you don't have to fight a strong throttle return spring. If the slide is not lifting up all the way at full throttle then there is a problem with the set-up. It is possible to pull the butterfly over center at full throttle and restrict your flow, but that is a setup issue not a design flaw. Finally, CV carbs are not set up to be lean because they are CVs, it is because of emmissions and they will need to have a larger jet, although I have had the opposite happen, too. My XJ550 Seca race bike needed to have the mainjets leaned out after removal of the airbox.
If you have a modified engine and exhaust then going with bigger carbs of any type will allow you to get more HP. In that case non-cvs are easier to buy new, mount and dial in from a baseline.
Of course all of us running CV carbs on our racebikes might be wrong.
AHRMA 412
Vintage racing - old guys on old bikes
CV carbs operate on a pressure differential between both sides of the slide diaphram. The only effect the airbox has is to provide one side of that differential. If you are running pods you will need to rejet.Power is based on airflow through the carb and the CVs have an extra butterfly that does restrict airflow compared to a non-cv of the same bore diameter. As far as throttle response goes a properly set up CV is virtually identical to a non-cv except you don't have to fight a strong throttle return spring. If the slide is not lifting up all the way at full throttle then there is a problem with the set-up. It is possible to pull the butterfly over center at full throttle and restrict your flow, but that is a setup issue not a design flaw. Finally, CV carbs are not set up to be lean because they are CVs, it is because of emmissions and they will need to have a larger jet, although I have had the opposite happen, too. My XJ550 Seca race bike needed to have the mainjets leaned out after removal of the airbox.
If you have a modified engine and exhaust then going with bigger carbs of any type will allow you to get more HP. In that case non-cvs are easier to buy new, mount and dial in from a baseline.
Of course all of us running CV carbs on our racebikes might be wrong.
AHRMA 412
Vintage racing - old guys on old bikes
