I would note that there is a big difference in "needing" it and "wanting" it.
The question was "could it be done".
My answer is yes it can be done effectively.
If the question is "Might some people prefer a balance shaft for comfort?"
My answer is yes for that too.
Interestingly, I'm forced to wonder if the sort of folks who LIKE vintage tech, air cooled, carbed, pushrodded big singles prefer the more visceral experience of heavy flywheels and heavy crankshafts in place of counterbalancer assemblies.
This technology is so obsolete these days even the 80s Japanese big singles are advanced by comparison.
For instance, if some restomod shop were selling turnkey Sportster adventure hacks with 800cc "halfster" thumper engines, carbs, kickstarts, and Baker 6 speed transmissions then they'd be marketing such machines as modern vintage artifacts...and experiences. Each machine would indeed be real world usable as a dual sport overland rig, but as an intentionally modern vintage experience too, and not just a travel appliance with an accompanying Motel 6 weekend mentality.
Ergo, anyone who actually purchased one of these things would be
intentionally looking for just such an artifact and just such an experience. Such a buyer would be
intentionally eschewing a smooth modern EFI Honda machine and experience.
Note that people keep spending a base minimum of 20,000 USD on brand new Ural hacks every year, and if you peruse any Ural forum you quickly see an oft repeated standard list of wishes that the Ural factory never delivers either because of government regs or too much production cost:
- A return to carbs
- A kickstart that actually works
- A 5 speed transmission, but preferably a 6
- More engine power
Yet year after year people keep buying new Urals. Modern vintage experiences are as important to some buyers as the modern vintage machines themselves.