it's not that they don't work. The carb design is a constant vacuum design, and the stock airbox was designed to provide that amount of vacuum. Going to pods without changing out the stock air jets takes the vacuum away. It takes lots of trial and error to get it right. Then there's the added variable of exhaust: stock pipes differ from aftermarket, baffles or no baffles.
Do LOTS of research on the whole pod filter thing.
Luke M
Used to have a 1979 CB750L, sold it as a parts bike, now riding a slightly modified 1984 VT700C. Network/Field Engineer. Central OH, USA, Earth, Sol System, Milky Way Galaxy, Universe.