oops.breather not cleaner....what a dope.

 

I just put a K & N air filter and intake system on my bike - and I expect it'll be a little noisier. ( I haven't run it yet).
I was due for a filter anyway, and the price for the stock one vs the K&N only about 6 x cheaper, plus with the aftermarket one I got a tuned plate and velocity stack.
Since I tend to keep my rolling stock until I can't use it any more, it'll pay for itself.
My thoughts, anyway.

 

I wouldn't worry about water. I have a round open air cleaner (similar to a Performance Machine one), been in torrential rain, never an issue.

 

Adding a/c alone does add few tq and hp. Same as good performance pipes alone. Same as only adding some fuel. Together, their is a definite sop gains. If you do these in stages, the gains may not be noticeable or slight.

OP, when you cleaned or replaced your air filter, did you see any oil residue? Enough to be concerned about, literally dripping from the filter and onto the motor? My bike never has spewed oil, before or after installing cams. External breathers are over used with the newer style metal breathers twin cams now have. Adding oil lines running down the engine and frame, adding a little filter that has to be serviced and tapping into the air cleaner support bracket only adds complexity.

I have a Rushmore cover and want to keep it so I installed a Crusher Street Sleeper III a/c. The breather lines are built into the back plate, very clean, no tubes. And unlike other after market a/c's, it has a breather channel built into the backing plate that directs any potential residue into the TB so it will not go onto the filter, or cover, or bike. It also has a large amount of filter element available. And, no rain sock needed and no extra noise from TB unlike open filters without a cover.

 

I was told by a salesman at my local dealership that the stock Rushmore intake is considered stage 1 because it flows like 15-20% more air than the football intake. I would just put a k&n air filter in your stock filter housing and call it a day unless you want to spend money on another intake for looks.

 

Arlen Ness Big Sucker (naked). You retain your original A/C cover, I have had this on 3 different bikes over the years and it does exactly what you want it to - deliver more air to increase power. I believe they are around $120, simple install.

 

I was running a stock '14 model air cleaner on my 103". I added cams, street ported heads, and S&S pipes, and the engine ran ok, but seemed weak in mid and top end rpm ranges. I put on an Arlen Ness big sucker and the increase in power was very noticeable. It is slightly noisier than the stock setup, but not enough to be annoying at all.