when you removed the fuel tank (and likely it got shook up well), to repair the carbs... did you completely dump the fuel, and flush the tank out with fresh fuel, and dump that also, and swab down the bottom inner corners to remove every bit of water and gunk in there? Or did you just add some gas to whatever was in there... ?
We commonly joke about the fact most people think actual fuel problems are electrical problems, and they start chasing electrical stuff.. and also vice versa; when in fact if a bike was running, retrace your steps, and there lies the issue... usually...
cleaning carbs is kind of a waste, unless you remove every speck and drop of old contaminated fuel from the system, meaning tank.