Are they rebuilt carbs?
Do they have a fully matched set of jets that you've visually inspected personally?
Are all the o-rings brand new, including the ones between the carbs on the fuel lines?
Are the gaskets fresh and intact?
Are the diaphrams intact and in good shape?
Have you personally bench synced these carbs prior to installation?
Regarding the bike:
Air filters and exhaust will change your air/fuel mixture ratio, so that means the stock jets may not be the ones you need for the bike to perform at its' peak potential. Work with DynoJet, and buy the correct Jet kit for your combination of bike and carbs. I spent DAYS fussing with jets before I bought their kit. After I properly installed their kit? I tuned the bike in under 2 hours. It's worth every penny.
I find that it's best to remove the jets yourself and visually inspect them to make sure they are properly installed, and are matching, and are the correct jet size. Never trust a PO when it comes to this. Since they're already off the bike, it's an easy task.
loudest143
(former 82 gs850g owner.)