1981 VB carbs on 1979 Engine?

[AndrewCB650]

Wow- it’s been a while. Hi all, Anyone know if I can run VB carbs on a 79 cb650 engine? Is there any difference in the 1979-1982 cb650 engines?
Any insight is appreciated! Thanks

[GeorgeSweety]

Hi, the inlet's spacing is different for the PD and CV carbs, the later cylinder heads had the inlets slightly farther apart.

[Volker_P]

True.
Here (option 3) is a hint how to mount them anyway without swapping the cylinder head. Swapping the head means some work but is possible, too, as intake spacing is the only basic difference between these heads, even the black RC08 heads should just fit.
I think throttle cables are different, too.
Be prepared that throttle response will be less direct/smoother for the CV carbs.