I don't think I would pull the carbs until I inspected/performed a few things.
There are more detailed forum threads to address each procedure. Check for sticky's and search 'The Verses".
1. Definately go through the tank vent system to eliminate possibility of POOGS.
2. Definately do replace the copper spark plugs with the iridiums.
3. Check to insure the battery charging system is functioning properly.
4. Check to insure that the carburator float bowl vent tube is not kinked, is clear, and is secured in the back of the right filter housing (ear). Also insure that the hose is not bottomed out. It is a good idea to cut the end of the hose at a 45 degree angle to insure hose-to-atmospheric pressure is not blocked.
5. Check to insure there is no fuel flow issue with the petcock during Idle (sufficient vacuum to open the petcock safety valve). Make sure your idle rpm is set to approx. 1100 rpm.
6. Do make the ignition pickup mod to .020" clearance.
7. Run the carburator mixture screws in all the way to seat them (gently), then run them both back out to 2.5 turns. This might clear some junk from the needle seats.
8. Assemble the 'frugal' carb sync tool, and ensure proper carb sync.
9. Check the fuel line routing to ensure no kinks or 'loops' in hose.
Let us know how it all turns out ... k?
'91 VN750 - Cosmic Splendor/Candy Wine
Done: Coastered, .020 ign., Iridiums, VM
Plexistar II, MCCT's, Relocated MOSFET
Will Do: Horns, Shave(maybe)