449/511 Breather hose mod

Speaking of tinkering, Ty and I were looking at a set of empty 449 cases the other day trying to figure out where oil could be re-introduced to the case without having to go through the oil fill hole. As you can see in the picture below, in order to change your oil you have to disconnect the hose from the oil fill cap which is not very convenient. I was able to find a quick release AN fitting for $59 which would definitely help here.





The only place we could find was part of the main inner case and would require a massive tear down in order to weld a drain bung in. Pre-BMW Husqvarna motorcycles have this welded in bung already. Fortunately I was able to locate a nice insert point on the clutch cover just above the fill point. This is partially blocked by a idler gear but will not impede the flow of oil back to the case and will not interfere with the fill cap, in fact the idler gear may prevent the back splash of oil. The case is also very easy to remove and a aluminum bung can be welded in easily (may even be press fitted with loctite). Two low pressure anodized flare fittings and some soft 304 stainless tubing will look nice and will be problem solved. Bill's Motorcycle Plus was kind enough to sell me a spare case cover to experiment with. Those who do not wish to modify their case covers can always use the quick disconnect above.




7707126 Clutch cover gasket
7715428 Inside gasket set
Yamabond

why not just unplug the PCV tube from the airbox and run it up and over a top frame tube and down again by the rear shock. Then plug the hole in the airbox.
Done, easy, and all of 5 minutes work. The fitting above seems as if it would negate the benefits of a PCV (lessen lower end latent pressure buildup). The drilling of a side case or the tube on my filler cap seem like overkill, but that is just me.

No worries Bill, this is really my fault for not just ordering everything new at the start of the project. These things just happen. I was just worried if the sight glass was a part I get in a week or a month from Husky. If I don't have one yet come case time, I will pull from Ty's stock and return him a the new one.

My oil fills my sight glass to the top and not a drop on the engine I have a plastic valve stem cap on the air box drain spigot. When I clean my air filter I just wipe out the filter box then spray some gunk and hose off then hand dry. I have found that leaning the bike way over to the right untill the footpeg touches will yield more oil out the drain hole, there is a bunch left on the top end and the only way to get it out is to make it go down the cam chain .

I have to lean way over in order to put 1400cc of oil in I have been running (1150cc is max fill). I am hoping with the breather mod + oil cooler I can get to 1892cc (2quarts). Should be able to run full throttle for sustained amounts of time with no torque limiter failures, no problem.

What would be the best area of the engine for the breather returns to re-enter the engine ? The cam chain area , clutch or filler area ? There must be a vent on the auxiliary oil tank for it to fill properly and for the oil to gravity feed back into the engine

If you look at my previous post here: http://www.cafehusky.com/threads/449-511-breather-hose-mod.25010/page-2#post-251822
you can see that pre-bmw's had the oil return built in. But the breather bottle is part of the frame which is ideal. You can drain back to the valve cover, I wanted to plug the breather and use a breather on the valve cover. But tolerances are tight there, might still be possible. The TC250's : http://www.cafehusky.com/threads/449-511-breather-hose-mod.25010/page-2#post-251845
return the oil right back through the same breather hole in the valve cover, excess gas is vented to the outside. I prefer re-burning this gas which has gas fumes in them, but a external filter could be installed instead.

The reason I used the clutch cover was because it was gravity down from my mount location on the side of the cylinder.

I grew tired of my breather bottle looking like a square, so this time I decided to shape it like an extension of the cylinder. I had the parts water jet cut, which should be ready tomorrow or Wed. Had them cut me a few extra pieces for bling.

Sounds like your on the right track now. I apologize for not reading your posts entirely , I like to think of ways of getting stuff done to

No worries wheelin, I am always open to new ideas, new progress.

At my old job before I up graded carriers I would clear fluid from gas lines out in the oil fields. Some fluid traps worked better than others. The breather bottled and dry sumps do the same thing. .....The only down fall is oil bypassing the filter.

I would be interested in seeing some of the traps you worked with.

My old design had all kinds of compartments and baffles. But this increased the complexity and weight. The new design uses 36" of baffle and is contained in one single piece. This is lighter, easier and should out perform the old baffle design.

The last pics of the cases , I think that's perfect the way the oil kind of gets held in a cloud and rains oil back into the engine

I'm not a 100% keen on cutting into my frame, though I'm not afraid to. But I could build the oil breather in either of the side tubes on the frame itself. I'll stick with my little bottle for now.

Speaking of cut frames, Ty has a 449 frame cut up in his shop actually. He designed a rear chain mod that rollers the chain upward like the old ATK's. The CTS still works perfectly, but the bike squats down into the corner like a regular MX bike. Last I heard, Husqvarna had a version of this frame and was testing it. No idea if it will show up in MY14.

The xlite breather pics on page two of this thread is a "trap" by design, although I am sure the trap wasn't designed to increase oil capacity at all, only catch what oil mist makes it there and in the event of a crash and the bike is up side down or laid over on the side of a hill the oil on the top end that makes it's way into the frame gets partially sent back to the engine while the rest gets the airbox and expansion chamber treatment. I will get you a pic as soon as I can draw one . I have to hit the hay for now