Although I am a big believer that the stock air filter in the R12S is not a limiting factor, I am goint to try a few more things with the engine and don't want to leave any HP on the table. I am not a fan of the oiled gauze filters because I know they will let dirt past. I came across this chart on the Pipercross site claiming an 8.5 HP increase for a R12GS, that is pretty incredible! I wouldn't expect that with the S but maybe there is some easy HP lurking. Anybody familiar with these products?
