| I think your summary is pretty accurate, Antonye. The filter in the tube is by all accounts the best approach. It provides a large surface as you say. Whether the filtration effectiveness of the stock filter foam is good enough for you, is an individual judgement, I guess. The piper cross replacement foam is certainly a finer foam, but will undoubtedly increase the "effort" slightly of pulling the air through it. How much difference this makes in terms of engine performance in the real world is questionable. It's most likely a worthwhile trade-off. I can tell you that the RS race filters are the same approach as the stock filters and the foam is very similar to stock if not the same. The advantage you gain with the RS setup is a very quick change of filters. Again, not really that important for street bikes.
I agree with you Antonye, using the stock setup with the Pipercross foam is the way to go. Just make sure the tank-to-airbox seal is sufficient. If you're worried about sucking in gravel, if the tank comes of in a crash, fit a tip-over cut-out switch.  |