Crankcase / valvecover breather

[Kurf]

I wonder if someone can answer my question :
Since I removed the original airbox and installed a K&N airfiler I do no longer had a place to go for the breather hose that goes to the filter...
What I did : I connected both hoses from rear valve cover to eachother with a T-joint so they both go to the oiltank...
QUESTION : wil this put some kind of pressure into the oiltank ( because there's no breathing into the open air ) ? And more important : can this do any harm?

like to hear from you : thought it was a nice (clever?) solution..... but I'm in doubt..

[Tcontrol]

Valve cover hose will pressurize your oil tank… would it cause damage? No idea…
would i do it?… no
what is recommended?… put an inline filter on the line and run a hose down to below the bike.. ( preferably not in front of the rear wheel)….

why..?…. If your idea was a good idea, don’t you think the engineers at yamaha would have done that to begin with?

[davej]

IMO it could cause damage by pressurizing the crankcase. You could develop oil leaks. That is doing the exact opposite of what the breather is intended to do.

[Lug Nut]

Just get some 5/8 fuel line and go from the top of the rear cylinder head straight down underneath the bike. Don't bother with a filter. I had one going to a filter and it got full and would sling oil everywhere. Just keep it simple. I would never put it back in the crankcase.

[Lug Nut]

[Duke]

All engines need to vent pressures accumulating due to blow-by. If it isn't venting, then pressure will increase and can cause blown gaskets and/or seals.
By running a larger breather hose going up hill to the neck of the frame, then back down to the air box, or bottom of the frame, will give time for the oil to separate from the air. I'll get a very minimum oil residue by doing this.
I started doing this 20 years ago after noticing oil on my air filter and haven't turned back.
With some of the parts stores, I'll ask to look at their pre-bent pcv hoses, and I can usually find a hose that bends 90 degrees then bends another 90 degrees with-in a 4" spacing, using that hose at the neck. I like a minimum of 3/8id, or larger, hose going up to the neck.
If a engine has a lot of blow-by from the rings then the more oil will be coming out of the breather.
This works for me, and have done this on several other Road Stars.

[Kurf]

Thanx: I will definitely change my current setup then

[Father Pobasturd]

This is what I did, as many other RSC members have. Run an auxiliary vent. It's right below the air filter.

[Kurf]

That’s nice. Will go for a similar solution

[Shores]

Leave the rear valve cover hose alone. Run the front hose down below the framework to a separate filter but not to the air intake unless you do what Duke recommended.

[Lug Nut]

This is what I did, as many other RSC members have. Run an auxiliary vent. It's right below the air filter.

This worked fine for me in town riding. However when on a long trip at Sustain Highway speeds day after day that filter became pretty full and just slung oil sludge all over my engine and side covers etc.

[Father Pobasturd]

I have not had that problem, though admittedly, my longest trip of late was 160 miles. I've been running this for 6 years. I'm not saying you're wrong Lug Nut, I know you ride more and further than me, just saying mine has worked fine.

[Shores]

I have a $2 PCV filter under my tank just behind the ignition switch and I probably clean it every 3 years or so and it is not very dirty because everything is uphill along the spine of the frame under the tank.

[davej]

In fact doing it like Shores said you can flip the OEM breather hose end for end and it will aim it up the backbone to the perfect spot uphill to mount either a breather element filter or PCV valve as Shores suggested.

[Kurf]

Thanx! This will be the way I’ll do it

[Popeye_5591]

This is a great solution. The OEM hose reversed and run up the spine. Th hose is just long enough to where you have options on what to do at vent end. I started with a filter like shore said, but ultimately it got saturated and misted oil on the cylinder heads. It really made a mess. I ended up taking off the filter and extending the hose down the frame and let it vent freely under the bike. Intuition will have you think it puts oil residue under the back tire and it is unsafe. In reality its not like that at all.

[BloodMoney]

I was thinking of doing a vented catch can. Came here looking for ideas.

[Lug Nut]

I was thinking of doing a vented catch can. Came here looking for ideas.

I like the idea of a filter catching it until it flung shit all over my engine on long trips lol. I did not like the idea at first of just having it go straight down because my thinking was then your rear tire is going to run over this horrible goofy nasty slippery oil and fuel combination. I've done this on multiple bikes and many many miles and never had any issue at all.