I have 28mm carbs with the pumper disabled. IMO, the pumper was used so overall they could use weaker jetting for passing emission requirements and not have the engine falter under acceleration. My pump needed rebuilding, but I read they can give issues when the bike is not used regularly with drying out and then taking ages to get going again, if indeed they did. I felt in part to fit some other float bowls I had and just do away with the extra parts to clean things up and get more consistency in running, given my bike is far from an everyday ride. If you jet accordingly and along the lines of the bikes before they used the pumper carbs, then I don't see a need to use that setup, although there may be some slight benefit in initial acceleration on paper, I doubt you would notice it. Given that it's good to run toward a rich mixture on an air cooled engine to keep temps down, it's probably wise to be running jet sizes that would be consistent with not needing an accelerator pump anyway.
So to answer your question, the 28mm carbs will run fine with out the accelerator pump, there were bikes that came from the factory with such a setup. To remove it just disconnect the linkage. To avoid a leaking diaphragm or similar and to remove some clutter swap the float bowls for the ordinary type. You will likely have to remove the nozzles, or the bowls will not seal properly as the nozzles protrude a little and the stock bowls have no recess for it to go into.
1978 KZ1000A2 Wiseco 1075 kit
1977 KZ650B1
1973 Triumph Tiger TR7V
1968 BSA Victor Special 441
2015 Triumph Thunderbird LT
1980 Suzuki SP400
Old enough to know better, still too young to care
