449/511 Breather hose mod

Eventually no matter what you do, oil will come out the breather hose simply because it cannot return back to the engine through the breather hole. Under filling the crankcase is a temporary solution, and though it may seem like a permanent solution to you now, engine damage will eventually be evident.

It would be safer to run the breather line as high as possible to a separate filter which has two inlet holes. Have one inlet attached to the breather line, the other a long drain back down to the bottom of chassis.

Then you would be able to fill your crankcase higher and when it pukes oil, let it. Better that than running the risk of sucking the oil pump dry during an incline/decline.

I am working on a more permanent solution to this problem which will allow us to run the full recommended oil amount listed by Husky engineers. A prototype system has been created (and actually works) which takes the atomized oil (oil mist) from the breather and pumps it back into the crankcase. I am hopeful to have a second proto in the coming weeks, time permitting that will attach securely and not look like an add-on.

http://www.cafehusky.com/threads/te-511-oil-in-air-filter.27215/#post-251527

Other than looking like crap, does oil into ( and subsequently, out of) the air box cause any problems?

As long as you don't foul your plug, shouldn't hurt anything. Pretty easy to install a seperate breather.

On my 2010 model, having the breather hose end higher than the breather would allow the oil mist to condense on the inside of the hose and then run back into the head, which it can do on a 2010, there is nothing to stop liquid oil from running back into the breather opening.

If on the new engines, the oil "cannot return back to the engine through the breather hole", wouldn't the oil mist condensation just start to fill the upward routed hose from the bottom to the top until it started running out the top?

Correct. And Correct, this information only pertains to the 2011-2013 449/511 platform, not earlier models.
Steep forward inclines or laying the motorcycle on its side while running will also purge liquid oil.

Originally I was told that the torque limiter was on the crankshaft, which it is not. It is near the center of the engine, down directly under the breather port. In order for gasses to pass out the breather hole, the gas must travel down a long oil tube to the center of the engine and must go through a .25mm gap along one side of the torque limiter end gear which is spinning and throwing liquid oil off. The gap is too small to allow oil to pass back into the engine without pushing it back with pressure.

Also while poking around in the cases, I found the oil pressure adjustment valve. This is really just a oil bypass valve with an adjustable spring that pushes oil straight back to the engine case. When the oil is cold and thick or if the pressure is too high during high rpm, instead of being pushed into the oil galleries, it's just returned back to the sump. Obviously some oil will go up the galleries, but flow is greatly reduced.

I see a lot of confusion on the oil levels, so I included a screen shot from the shop manual on oil level. Oil is to be checked when heated up, as Motorsportz commented. Personally, I would run the heated oil level to the top of the sight glass and not the min mark due to the oil pump pickups being elevated and not at the bottom of the sump.

This would indicate that the condensed oil mist has a way of dripping back into the engine.

That's a good question Kelly, I'm not sure. I can fill my breather tank up with oil and it will not pump back into my 2012 511 on its own. After adding the pumping mechanism, no matter how full my breather tank got with oil, the oil was always returned to the case. It isn't year specific either, it happened to Ty on earlier models as well. Maybe clearances are tighter on some engines, I really don't know. On my engine, oil up the breather tube is an annoyance which I am attempting to fix. I am hopeful my efforts helps others as well.

If you look at earlier 250/310 models, they have oil recovery systems built in that Husky designed. I'm not sure if BMW originally had this design on the G450 or not. Or if some of the changes that Husky implemented to the 450 engine caused other issues.

Or it may not be condensing at all and just evacuating to the air?

Oil didn't drain back on the 310 either, so Husky took elaborate measures to get the oil back to the crankcase. I think this is a BMW issue and not Husky's.

It is an EPA thing. Positive crankcase ventilation is actually a good thing, but I'm not too thrilled how bmw did it. I think I am going to consult with my husky partners and see if the vent can be moved to the valve cover. It will still work in my design, maybe even better. Another option is the Yamaha method of sucking it into the exhaust, EPA should be thrilled about that.

The TC's still use the oil capture tank, but they just let it squirt out the bottom of the chassis. On an SMR, this may lead to STS (slippery tire syndrome).

Here's a link to the original BMW parts list with prices:
http://www.maxbmwmotorcycles.com/fiche/DiagramsMain.aspx?vid=51781

Interesting BMW lists 5w-40 as the recommended oil.

Graves motorsport make an air/oil separator tank for supermoto Yamahas, it catches the oil from the crank breather, also has a vent line to prevent creating a vacuum. It has a small return tube to return the oil to the engine via a modified inspection cap.

http://www.supermotojunkie.com/show...Recirculation-and-Catch-Cans&highlight=graves

Not cheap though; http://www.gravesport.com/Graves-Motorsports-Yamaha-YZ450F-Supermoto-Oil-Air-Separator-Kit.html

Thanks Caiman. The Graves motorsport unit (shown below) is very similar to the breather I am working on but smaller. Mine mounts similar, but to the right side of the cylinder and is bolted on rather than strapped. My valving is slightly different in that instead of a drain back, oil is actually pumped back in. But overall, this is definitely the solution. Husky's design incorporates use of the frame, but using one side of the engine cylinder works just as well.

I like the tropic and and will be ordering one when a product is available however i have never had a problem with my SMR 449(I race Supermoto on mine)! Wondering if it's because of the larger 511 piston etc?

The 511 does push slightly a higher volume of gas than the 449 and is even noted on SpeedBrain's website to remote the oil breather to a different location when upgrading to their 480cc kit.

On the Yamaha's, which the Graves Motorsports oil recover system was created for, it basically allows them to run their crankcase oil at a higher level, rather than lowering it to the bottom of the sight glass like we do. The G450 motor was originally designed to hold 1200cc(1150cc) of motor oil, but there is no way it will hold this quantity without blowing it out the breather hole. I am attempting to raise the oil quantity back to the original 1200cc by adding a recycling system.

On a side note, when testing this system, I am able to fill my crankcase beyond the top of the sight glass cold. Oil that was blown from the breather was collected and returned back to the crankcase automatically.

Just looking at my SMR, with the full Ti akra powerbomb thing there ain't much space left on the right side of the engine for a tank like the graves one.