Does anyone know if a K&N 1508 in the stock cover is significantly more restrictive than say a Fuelmoto Billet AC or Arlen ness Big Sucker?? Im looking for a free flow AC but don't want to add any additional noise. I'm thinking the K&N 1508 may be enough vs the stock air cleaner even though its likely not as free flowing as other's...thoughts, experiences?

Thanks
JG

 

I use the K&N 1508 filter and I'm often beyond 5,000 rpm because this filter breathes well. It's quiet, so it's perfect for long trips and if I have more Silica in my oil, well, "so shall it be" ...
I think the way you break-in your engine is more important than the rest. Those who profit from all gears through the entire range of engine speed have more than enough to enjoy a well sought touring bike.