I have an Arlen Ness Big Sucker Breather on my 08 EGC. When I first installed it I left the Black back plate on as I believed the instructions did not say different. When I took the bike in for service a few months ago, one of the techs recommended I remove the backplate informing me that if I don't then I will have problems later. You guessed it, I got home and immediately removed the backplate. Well, I was looking at a link to Arlen Ness and the picture had a breather that appeared to have the backplate behind it. I went to the website and sure enough it is there. Who is right? Harley or Arlen Ness. I need HELP! Do I leave it off or do I put the thing (backplate) back on. Here is a picture of the backplate I removed.


Here is Arlen Ness Picture on the website (if you look closely then you can see the backplate)

 

I'm looking at the big sucker so I'm interested also... bump.

 

The tech told you that because the SE backing plate requires removal of the bracket. The SE backing plate will not sit flush against the throttle body and leaves a gap about the thickness of one gasket unless you remove the bracket. If Ness compensated for that somehow and your unit sits flush and sealed by the gasket against the throttle body and there is no gap then you won't have a problem.

 

Right!
I don't recall removing the bracket when I installed my ANBS.
You have to look and see if it sits flush.
I did.
But I don't remember removing the bracket.
Jusr sayin.

 

Just a wild guess, but if you took an ANBS back plate and an SE back plate and put them side by side, I bet AN compensated by making the stubs where the breather bolts go through a gasket thickness shorter than the SE, thus allowing it to sit flush.

 

When I removed the backplate the banjo bolts did not go flush, there was a gap. Later I put spacers to remedy the problem but I think with the backplate on things were better. I need to know for certain if I need to reinstall the backplate!

 

I have the ANBS on mine and did not leave anything on as for the AN sits flush on mine.

 

Mine fits right with the throttle body support plate bolted up behind it. From what I remember, the instructions specifically said NOT to remove it.

 

Your right Dawg.
If I recall correctly, I remember reading (past posts) about people installing one of the backing plates and breaking the stubs off. Not knowing to look if the intake area was flush or not. Of course this was someone elses fault. But we won't go there.
Mine is sitting in my locker at home. Since I just returned to work this morning. I can't look to see if that bracket was among the peices I took off. But for some reason - I dont think so.

 

The 08 OE backing plate stays on with the BS install.