I have a 2015 Ultra Limited. If I do a stage 1, why do I need to change the air breather, if the stock breather on the Rushmore bikes is supposed to be High-Flow? I was just looking at the FP3 Tuner and it also calls the stock breather High-Flow.

 

I have a 14 ultra limited that I did a stage 1 on. I kept the stock air cleaner and just replaced the filter with a K&N filter. Had the bike dyno and it runs awesome. I was told that the stock air cleaner flows just as good as an aftermarket stage one. It's now putting out 96hp. With 112 ft lbs. I used Mastertune TTS, Screaming Eagle Street Cannons and stock a/c with K&N filter. Good Luck, enjoy the bike!

 

Did you get a dyno?

 

I called Fuel Moto and asked the same question, they said the stock air cleaner does flow more air than previous models but no where near as much as High Flow AC Like Screamin Eagle, Arlen Ness or Fuel Moto.

 

the 14+ air cleaner flows about 180 CFM with stock filter.

this seems to be matched to the motor demand for air.

previous stock air cleaners were more restrictive ( about 150~160 cfm) and for a stage 1 needed to be replaced.
Ness and Screaming eagle air cleaners flow about 250 CFM which is more than the motor could ever demand.

Seems the stock air cleaner is suitable from a power point of view.
Some of us prefer an oiled reuseable filter media- I use K&N's which seem to do a great job with the desert dust here in AZ, Being an older model I replaced my stock air cleaner with a ness big sucker- under $120 on ebay from easternpc

Mike

 

One a stage one like mine with just a K&N element change there is more than enough air flow (my general statement).
The statement you made is probably mostly true because "no where near as much as High Flow AC" is a relative statement (What is the application, how much air do you need?).
If you do just a stage one and compare a stock air cleaner like mine with a K&N element to a "High Flow" one like Fuel Moto's in a seat of pants test (Like I did), all I noticed is more noise with the high flow.
I like Fuel Moto but they have to SELL to people who think they need this stuff.

 

If you want to do it right you need an actual high flow a/c.

 

It all depends on what you're looking to accomplish. If you're just looking for a little better running bike and not going to change cams, the stock ac on the 14 and later Rushmore is going to get it done. All the other air cleaner setup's are either feel good or look good items if you're staying stock.

 

Here is a true statement...

on my 2009 103 with the stock intake (moved from sea level to 4,500) and it pinged and pinged REGARDLESS the octane.

put a 2015 stock intake and the ping vanished like a fart in the wind.

my question is... just how much air flow is needed... there is but so much real-estate in the jugs.

 

The FM kit that I use opens up slots in the back for extra air flow while using the stock shell. What I've always wondered is what the negative effects are of pulling that hot air coming from between the jugs. Back in the day, we always tried to feed the engine the coldest (densest) air we could...