Main Motorcycle: Black '04 Sprint RS
Join Date: Jul 2007
Location: Austin, TX
Other Motorcycle: Blue '04 Sprint RS
Too low octane will cause ping or knock under some circumstances. Too high will cause carbon buildup over time. There's nothing better about "premium," it's just harder to ignite. Usually best to stick with the recommended mid-grade unless you've installed high-compression pistons or a turbo or some other mod that needs higher or lower.
K&Ns flow gobs more air than stock when clean, but let lots of junk through. Gradually, they fill up with said junk, which improves filtering but decreases airflow to about the same level as a stock filter. They definitely add an air of mystery to the proceedings, I'll give them that.
Might be slightly easier to pull the up-side float bowl without pulling the carbs, but only slightly on the Trophy.