My Fatboy has NO breather hoses
 

I just ordered the K&N air filter element for my bike. In doing my research, I discovered that I was missing the sealing ring on the air cleaner cover, so I ordered one from Ronnie's.

But now I've also discovered that I have no breather hoses behind the filter element. None.

They obviously came stock with the hoses because Ronnie's lists them on their site. But why would someone have removed them? Also, will the performance be any different if I put some back in?

Any ideas?

Are you sure that a PO didn't reroute your breather hoses to ground instead of the back of the air cleaner?

I'm not sure I follow. I've heard of people doing that, but when I pull the OEM filter element out, I don't have the two black hoses I keep seeing in the videos. The two holes they're supposed to go in on each side are wide open. Ronnie's also shows them in the parts diagram for my bike.

How can I tell if someone has done this?

Can you post a picture of the right side of your motor?

As for hoses going into the back of the OEM filter element that's not important.
What's important is to close off the holes in the backing plate so that all the air going into your motor goes through your air filter.

I'll take a shot after work today and post it.

Thanks.

Okay, I've looked into this.

If a former owner had done this, where would the hose(s) be attached? Somewhere on the head(s)?

There are a couple banjo bolts (passage for fluid to pass through the middle of the bolt threads) in each head. Usually connected to the carburetor back plate via some solid plumbing. The plumbing on the left has a nipple, this connects via tubing to the backplate of the carb. Oil pukes through this nipple/tube at times, so many folks Re-route the tube to the ground, instead of the carburetor back plate.
If that’s what you find, seal the hole on the carburetor backplate.

Thanks. I'll post a pic tonight so maybe you and the others can walk me though it.

Okay, here we go. These are some decent closeup shots. I've linked them because they're somewhat large. Please let me know if you need to see a shot of anything else.

Click the thumbnail below to see the larger image:

EDIT: I WISH THIS BOARD WOULD QUIT HOSING MY CODE!!!!!

Just click below....

http://www.southtech1644.com/files/cleaner1big.jpg
http://www.southtech1644.com/files/cleaner2big.jpg
http://www.southtech1644.com/files/cleaner3big.jpg
http://www.southtech1644.com/files/cleaner4big.jpg
http://www.southtech1644.com/files/cleaner5big.jpg

That’s a stock airbox... you don’t need the hoses.

That looks stock to me.

See those hollow bolts at (roughly) 10 and 2 o'clock? Those are the head breather ports. Those are hollow bolts that allow for flow of crankcase gasses from the engine into the airbox.

It's not exactly the same thing, but this vid I put up a few months ago talks about this stuff.

(Ignore the fact that more than once, I say "exhaust gasses" when I mean "crankcase gasses")

Thanks, guys. This makes me feel better but it still leaves me with a burning question.... why does the Ronnie's parts diagram for my model show the breather hoses?

http://www.southtech1644.com/files/breather.jpg

This diagram is specific to the 1994 Fatboy. But I've also noticed that some videos show the hoses and some don't.

Also, I have the K&N on order. Can I expect any performance increase?

From an air filter???
No.

Probably not. I suppose its possible if your old filter was packed tight with dirt or something.

Its all about fluid flow, and unless your airfilter is currently the chokepoint in your system, a new one won't make any difference.

The real problem is that stock airbox. Its designed to be a sound muffler.

You have to look at the whole system: Intake / cylinder heads / exhaust. It all has to work together as a unified whole.

I wonder if that tube in the diagram has something to do with CA emissions.

OK, look.....
the hoses you are asking about take the ventage from the heads and injects oil fumes into the air filter.
You still have the clunky air box behind the cover, and the hoses are a built-in feature.
What you are missing to do what is pretty common, is a Screaming' Eagle air cleaner backplate and a fitting that links the heads and has a hose barb. That is where most of us "vent to atmosphere".

What THC meant to tell you is that a KnN filter by itself will not register much on the butt-dyno. It does its best as part of a balanced package (cam, pipes, air cleaner, carb reset).

THC is just a little cranky tonite........ he just blew up his starter.

Thanks, everyone. this puts my mind to ease a bit. I might look at upgrading the entire air cleaner assembly at a later time.

Do yourself a favor and upgrade the whole thing to an S&S Super E!

I heard that an S&S could cause a kick back, destroying the starter.

He'll be ok if he doesn't get the carb that's already attached to a V111!!!!!!:D

:icon_laugh: :icon_laugh: :icon_laugh:

https://cimg1.ibsrv.net/gimg/www.hdf...36ca432450.jpg