Slim air cleaner
Road Master
Joined: Feb 2011
Posts: 784
Likes: 10
From: SE Pennsylvania
Just curious as to how it does that? I removed the stock back plate, air cleaner, etc., and installed the SE back plate, hoses, filter, etc.. How does this increase hot oily air intake into the engine vs. other air intake systems?
Sorry if this derails the original message.
.
Elite HDF Member
Joined: Apr 2012
Posts: 3,986
Likes: 709
From: San Diego
Just curious as to how it does that? I removed the stock back plate, air cleaner, etc., and installed the SE back plate, hoses, filter, etc.. How does this increase hot oily air intake into the engine vs. other air intake systems?
Sorry if this derails the original message.
.
Sorry if this derails the original message.
.
It is counter-productive to performance and to engine longevity. Engines like cool dry air.
__________________
DKCustomProducts.com
DKCustomProducts.com
2nd Gear
Joined: Jul 2012
Posts: 6
Likes: 0
From: WA State
24v nailed it. Almost all aftermarket Stage 1 A/C's route the hot oily air back into the air cleaner, just like the stock air cleaners do. This is to please the EPA, but it is NOT how an internal combustion engine was designed to work.
It is counter-productive to performance and to engine longevity. Engines like cool dry air.
It is counter-productive to performance and to engine longevity. Engines like cool dry air.
Last edited by Archie01; Sep 19, 2012 at 11:29 AM.
Novice
Joined: Jan 2012
Posts: 22
Likes: 1
From: Central, MA
Arlen Ness Big Sucker kit does this by eliminating the breathers all together?
If this is the case, why not just plug up the breather holes
on the SE AC ?
May be a bad idea, as nowhere to vent the crank.
How does ANess get away with those breather bolts?
Anyone done this?
If this is the case, why not just plug up the breather holes
on the SE AC ?
May be a bad idea, as nowhere to vent the crank.
How does ANess get away with those breather bolts?
Anyone done this?
Tell me if I have this right... Your Hi Flow 587 kit prevents hot, dirty air from getting back into the intake because it uses the brass mesh breather bolts instead of breather plugs (like on the SE kit) and the Arlen Ness Big Sucker kit does this by eliminating the breathers all together? I just installed a SE Stage 1 kit on my Slim with a set of V&H BSS pipes and had the dealer do their Stage 1 download. The bike runs great (for now) but after reading this thread, I would like to prevent the carbon build up on the pistons. Also, if I install a 587 kit to replace the SE kit, will the dealer download need to be changed or will it be ok as is?
(also available with the HiFlow 587 is the traditional hose and filter breather system)
The SE and the Ness BS both vent the hot oily air back into the engine via internal passageways built into their backplates. This is to satisfy the EPA, but it is NOT good for performance or for the engine.
Both the SE and the HiFlow 587 flow more air than your engine can use, so if you are happy with your tune right now, there is no need to change it when moving from the SE to the HiFlow.
Road Captain
Joined: Oct 2011
Posts: 523
Likes: 1
From: kingston ontario
just out of curiosity is there a way to catch the oil coming out of the highflow or do we just wash the bike more often?
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Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
Likes: 4,573
From: TOAK western branch
It is a compressed brass bead filter. Only air passes through it. I imagine that if you never washed your bike you might see a bit of residue. That style of breather has been used for many years in other applications. First time Ive seen it on a bike. Great idea!
