The CV carbs work fine all day long as long as they are put together competently. No insult intended of course.
Assuming you mean swapping a set of earlier SOHC carbs for the later DOHC VB series CV type. Won't work, the carb banks are different in so many ways you could fix your CVs 4 times right before the others would ever work. If the later mechanical linkage type the bank won't clear the tank bottom. They are not correct width, nor intake same size hole and don't fit the airbox either. Not only that, they are smaller, you'll lose power doing it.
FYI, after playing with DOHC engines for years one finds out that most mess with the carbs when there is no reason to do so, commonly the engines have other faults that are blamed on carbs. Ergo, work on them till the end of the earth and no way will carbs fix engine troubles that are not carb induced. Sound familiar?
Reason #1 is engine down on compression due to bad valve settings/other. CV carbs absolutely MUST have a good solid engine pulling draw on them or the carbs simply refuse to work right. The slides cease to lift thereby making for insolvable jetting issues when it goes super rich. The super rich then makes the slides drop even more and a vicious cycle there. Dropping stock airbox just makes it worse, the box actually makes the carbs work better.
A compression test and if engine not making 140 psi or better in all holes then forget the carbs and work on the engine.
