Sportster air filters..stock or aftermarket which is best?
 

Was wondering that maybe the stock air filter gives the best all round performance and reliability....anyone got an opinion on this?

What you have to bear in mind is that the stock air filter is contained in what amounts to a muffler, to reduce engine noise and help comply with noise regulations. If you ride your bike stock, your statement is correct, however if you intend doing any tuning mods then replacing the airbox with, say, an SE air filter, will give a little extra performance (along with other things). There are SE versions that retain the stock cover, if you want to minimise cost, or prefer the stock appearance.

The stock air filter and housing do not give good performance, some aftermarket air filters are better than others as some are more for looks and some are more performance orientated.
Look at DK's site and Hammer Performance as well as NRHS for a selection of true performance air filters and housings.

I have a DK air filter on my 08 and it made a (somewhat) noticeable difference. I still have the stock pipes, so I didn't have to do any remapping or anything like that.

Thank you for the shout out :icon_banana:



There are only a few companies making true performance intakes anymore.

DK Custom
NRHS
Hammer
I don't know of any others.

Pushing blow-by back into the air cleaner is counter productive to performance. What comes out of the breathers is primarily exhaust and oil.

It is also hot. Engines perform better with cool dry air and gas...not hot oily air and gas.

Additionally the exhaust gas has a lower oxygen content, displacing oxygen on each combustion stroke. Another performance robber.

Oil will build up carbon deposits on the pistons, leading to pinging/tuning problems down the road.

It's just a bad idea...the only upside is you make the EPA happy.

I would go with a free flowing Air Cleaner like the Outlaw 587 or the 636v, these Air Cleaners do not allow all the hot, dry, oily back in. The pictures below are of a twin cam but will be the same concept for your sportster. Hope this helps you out:)

Before venting externally.
http://www.dkcustomproducts.com/images/TwinCam1M3.jpg

After venting externally.
http://www.dkcustomproducts.com/images/TwinCam2M3.jpg

Kelsey

Is the rough crafts one any good plz

I replaced my stock with a Screamin' Eagle Stage 1 Sportster kit 29782-07 for more airflow.
I had an S&S teardrop on my 2009 FLHTCU.
I had an Arlen Ness Big Sucker Stage 1 on my 2006 FLHT.
I ride in the rain quite a bit , so I like the fuller coverage systems , I wanted this bike to look stock , because I like the look.
All 3 worked as claimed and certainly flowed more air than stock.
I'm partial to the closed breather system , just a personal preference.
Mick