What is this hose?

[markdjr]

I have a 78 GS550

There is a hose coming off the top of the engine, it is not connected to anything, but it has a clip on the end as if it had been attached at some point. It looks like it is spewing exhaust, or some kind of smoke. Any ideas? Should it be connected somewhere?

Thanks.

[BassCliff]

Hi,

That's the breather hose. Connect it to the snorkel on the top of the airbox.


Thank you for your indulgence,

BassCliff

[markdjr]

Ive got pods and 4-1 installed. Sorry I should have included that originally. Leave it or move it somewhere else?

[loungeguy69]

Dump the tube. It's for the crank case breather.

Get a breather filter from Dennis Kirk, Bike Bandit, etc. Or find something from your local auto parts store and install it close to the origin of the breather tube (near the valve cover).

[markdjr]

I'm not quite sure I understand. It seems like it is exhausting, I need a filter? Sorry I am not that familiar with the breather.

[chef1366]

It's just a crankcase breather. It used to go to the airbox. It let's all the piston blow-by and crankcase pressure to be relieved. If you block it off you'll blow out gaskets. Think of a pc valve on a car.
If you lost the airbox I ran mine to that area into an old tupperware container with a hole cut in it. It'll keep oil off things.

[BassCliff]

Let's see if this link works....

http://www.denniskirk.com/jsp/tpl/cmn/prodlist.jsp?store=Main&catId=414&leafCatId=41401

Thank you for your indulgence,

BassCliff

[chef1366]

Let's see if this link works....

http://www.denniskirk.com/jsp/tpl/cmn/prodlist.jsp?store=Main&catId=414&leafCatId=41401

Thank you for your indulgence,

BassCliff

The 3/8 size will do ya

[loungeguy69]

I'm not quite sure I understand. It seems like it is exhausting, I need a filter? Sorry I am not that familiar with the breather.

The pressure in the crankcase alternates from positive to negative (blow - suck) as the pistons move up and down. The crankcase breather allows the cylinder head to exhale and inhale in accordance with the changing pressure. This is why it appears to be 'exhausting' but is actually 'intaking' also. The breather filter stops dust, etc, from entering the cylinder head.

[doctorgonzo]

The pressure in the crankcase alternates from positive to negative (blow - suck) as the pistons move up and down. The crankcase breather allows the cylinder head to exhale and inhale in accordance with the changing pressure. This is why it appears to be 'exhausting' but is actually 'intaking' also. The breather filter stops dust, etc, from entering the cylinder head.

Yep.
I ran mine back to under the battery box.

[GS700E Lover]

I have that filter also. There is a screw on the end, and I used a heavy duty wire tie to tie it to the frame so it did not bounce around.

[Clone]

You have to have that breather hose open, and to keep dirt from being sucked up the hose and ending up inyour crankcase or choking the hoseyou will need to have a filter on that hose OR what I did do with one engine was to drill a hole in the pod cap just smaller than the hose I was using and worked the end of the hose into the cap of the pod. So all the oil vapor was burned in the engine and when it did suck it got filtered air from the pod.

[Skyboy8950]

I've always heard that it was for "emissions control". If you burn the air that comes from your engine, it is less efficient than fresh air. I rather just put the filter on it.

[Clone]

Emissions? We don't obey no stinking emissions regulations.
All engines have a closed loop that take crankcase emissions and send them right back through the intake, none of that vapor is vented to the atmosphere anymore, not since somewhere around the mid or early 70s