I've worked on other's Hondas and had a Shadow with a carb before my FI bird. It only takes one flooding for the plugs to foul on that Shadow, the plugs are toasted. I got so tired of replacing em, I kept 4 in my tank bag and would swap em out whenever they fouled, clean em up for next time. Comparatively, to a car, the spark is horribly weak. Even had a friends rebel that fouled only one side from my garage to the end of the culdesac. Swapped em, clean the fouled one and it's been running ever since. Go figure. And he was telling me I didn't know what I was doing,
Even though those carbs were set correctly, with the weather warming and all that it might be a good idea to get practice on cab adjustment and plug reading.
Johnny