Breva/Norge airbox question

[vitek]

Hi folks, I wanted to ask, what is the purpose of the right outlet on the back of the airbox? I was trying to find some info from the service/workshop manuals but with no luck.
The hose from the left one leads to the oil recovery tank but the right one is going back and downwards.

[paulbricey]

Usually the airbox drain is for water/condensation/maybe some oil (that dodged the blowby separator) & runs to a plugged pipe that may need to be emptied every now & then (It's plugged to stop unfiltered air being sucked up into inlet air. As you say the other pipes relate to primary blowby oil/emulsion/gases separation which return oil/emulsion into sump & 'dirty air' back into inlet.

[vitek]

I am not talking about the drain. And since it is on the top of the airbox, I wouldn't call it a drain. Drain port is on the bottom left (part no. 16 on the right schema). What I am curious about is the top side. On the image that I've posted, there is the hose (part no. 2 from the left schema), connected to the left-side "port". But I have no clue about the other hose, that I have connected to the right "port". Neither there is an information in the schemas/service part catalogue, nor in the manuals. Even in the workshop/service manuals, there is only one hose (part no. 2) connected to the airbox from the top that goes to the oil recovery tank.

I am thinking about some kind of breather, but I am curious what is it for. :)

P.S.: Sorry, I've noticed that the picture I've attached to my first post was not displayed. Now, it is fixed.

[Huzo]

I’ve wondered that too.

[PJPR01]

That second nipple on mine is completely blocked off at the bottom with the original plastic of the box so it cannot be a breather of any sort.  Is yours actually open into the airbox?

I think it's just a form stamp on the plastic box...no idea why they did that unless there were some other models that used that same box that actually had it hollowed out and connected.

Adding a second breather I don't think does anything as the intake is blocked, at least on mine.

[vitek]

That second nipple on mine is completely blocked off at the bottom with the original plastic of the box so it cannot be a breather of any sort.  Is yours actually open into the airbox?

I think it's just a form stamp on the plastic box...no idea why they did that unless there were some other models that used that same box that actually had it hollowed out and connected.

Adding a second breather I don't think does anything as the intake is blocked, at least on mine.

You are right. The nipple is sealed. I changed the oil pressure sensor yesterday so I removed the airbox and did a little inspection on this. I wonder why some of the previous owners put there that hose. It doesn't make any sense, maybe it was ment as a hideout for spiders over the winter. :)

So, I put the hose away. It was like removing the appendix.

[brider]

Eureka! What timing...I was just about to post a thread almost about this same topic. I was going to ask "Should a hose go between these 2 ports? Mine currently has none.":





Guess I better add the missing hose!

And yeah, I wondered about that phantom port, but saw pretty quickly that it was non-functional.

[brider]

Related question: Any suggestions on how to line up the tank mounting bolt when re-installing? First time I did it the mis-alignment was not as bad as this time, looks like close to 3/8" mis-alignment which is gonna be real fun to try to jamb the bolt in, NOT cross-thread, while pushing the tank forward (& not push the bike off the centerstand). 

[guzzisteve]

For tank install to line up you can trim off some rubber from the bumper on front mounting both sides. Make sure where you trim is facing to the rear as to let tank slide forward.

[John A]

If the tank mounts like an EV with 2 rubbers on the steering neck. I put some silicone lubricant on the face of those so the tank slides forward easier

[PJPR01]

Once you are certain that the front of the tank slots are fully on the rubber bushings, then use a medium width philips screwdriver into the tank bolt hole and lean it a forward to align as best as possible.  If you are struggling to get it onto the rubber bushings, then you may have either wiring or the airbox slightly protruding and preventing it from moving forward all the way or your vent hoses from the bottom of the tank are preventing it and have to be re-routed, worthwhile checking to avoid anything being crimped.

Once that is done, remove screwdriver, insert bolt and gently push on the bank of the tank towards the front of the bike while starting to thread in the bolt...works like a charm to get it started.  If it requires immense pressure, then something is likely blocking the mounting on the bushings.

A bit of light grease on the bolt doesn't hurt either to eliminate friction in the threads.

[PJPR01]

Eureka! What timing...I was just about to post a thread almost about this same topic. I was going to ask "Should a hose go between these 2 ports? Mine currently has none.":





Guess I better add the missing hose!

And yeah, I wondered about that phantom port, but saw pretty quickly that it was non-functional.

Yes...there is a hose that connects the left nipple to the front of the airbox breather on top, and is anchored onto the airbox middle screw with a clamp.  if that's missing, easy enough to get some flexible rubber hosing to connect the two.

[DoubleGuzzi]

If it requires immense pressure, then something is likely blocking the mounting on the bushings.

.. or you have a plastic tank swollen by ethanol, which can only be refitted by using a scissors jack - as per my Triumph 955i Sprint ST.  Scary times!