Engine Breather

The amount of air (actually blow-by vapour) should be negligible. If it isn't you have bigger problems!

By venting the crankcase in through the engine fire you burn any crankcase vapour, including the oil mist in it and improve hydrocarbon emissions. It also means you don't see an oil slick from the breather.

The problem with the breather is not so much a reduction in performance as it is REALLY bad when you drop it on the left side past horizontal and a significant quantity of oil flows into the air intake. If you are lucky it wil just make it hard to start. Less lucky is completely oiled up spark plug or hydraulic lockup.

I did the mod last week, then put it all back the way it was, I just dont like the idea of an open hose to the top of the engine, I would be much more comfortable with a filter or some kind or non return valve or something in the re somewhere. of course it helps not to drop the bike to avoid the problems, I just keep telling myself that.

Azza.

When I got mine it was open to the air via a great swolen dangling dribbly hose with dirt up it. I put it back to original and I have only regretted it once when I fell at the top of a big hill. Luckily it roll started by the time I got to the bottom.

One thing to watch out for is with the engine venting into the frame tube you tend to end up with a small puddle of oil condensed in the tube below where it opens into the carbie. Not a problem until you do a stoppie. The puddle splashes straight down the throat of the carbie & you dissappear in a huge cloud of smoke. Not very cool if you are trying to show off to your mates...

I am thinking that recycling the oil fumes back through the motor might be why it has carbon on the exhaust seats along with a rich mixture accelerator pump etc. I have read oil in the mixture also can cause detonation. I am looking at putting a catch tank and valve, Dale Linaweaver has a post on here about this.

Cheers ,spanner

awilksch said:

I did the mod last week, then put it all back the way it was, I just dont like the idea of an open hose to the top of the engine, I would be much more comfortable with a filter or some kind or non return valve or something in the re somewhere. of course it helps not to drop the bike to avoid the problems, I just keep telling myself that.

Azza.

Click to expand...

This pic shows the addition of a one way high speed check valve which also has the effect of creating a slight vacumn. Check the doc for the part number or find the thread "Crankcase Venting 101" in the mechanical section. You can finish off this set up with a K&N breather filter if you like.

Adding a one-way high speed automotive check valve to the crankcase breather has proven to alleviate most if not all of these symptoms. Click [/img]http://www.husaberg.org/modules.php?name=Forums&file=viewtopic&t=1110 for info.

I like the way you have it venting to the chain, but I think I will stay un - modified, given that there is little benefit from the mod.

Adding the one-way high speed check valve will help and is a definite benefit even if you leave the end connection unmodified.

I've been working on something with the KTM which would easily transfer to the Berg. Obviously, no airbox to mount it in but it is worth it to have the breather line go to a catch bottle, especially if you are running supermoto.

on my 2004 650 i only stopped the hose from the top of the camchain the other is still open then it stopped throwing oil into the frame...

No-angel said:

on my 2004 650 i only stopped the hose from the top of the camchain the other is still open then it stopped throwing oil into the frame...

Click to expand...

is this solution good?

could the engine breather be the cause of an high oil consumption? i removed the air filter and there was a bit of oil all around

What do the Supermoto Racers do with the breather? Thomas?

No-angel said:

on my 2004 650 i only stopped the hose from the top of the camchain the other is still open then it stopped throwing oil into the frame...

Click to expand...

I have done this with my 04 550 and the oil consumption over my first test of 300 was virtually nil.
Prier to this it was using about 150ml of oil to 300 miles.

Regards

Sparks.

fwiw, adding a significant length of tubing of the same size or smaller than the vent spigot decreases the frequency response of the venting system. in other words, the rapid changes in pressure seen at the spigot are dampened to the point where there is no venting. remember, the stock system goes from small diameter to large.
there may be no obvious problem doing it this way, but to emulate a free flowing system and keep internal engine pressures more constant, don't add a lot of resistance to flow.

so stopping the camchain one, and letting the other one connected to the frame could work?

i asked to a couple of husaberg mechanic and they told me that they block one and plug a tube to the other which flow into a can

I've got to say, I love these costly and convoluted, but nice looking mods some people make. :wink:

In my supermoto racing days we used to buy a bit of hose, scrabble around and find an old plastic coke bottle or can of redbull or any beer can of your choosing and stuff the end of the tube in there. Ideally, just loop the tube over the frame in front of the tank and down to just behind the radiator on the other side of the engine where this old bottle is zip-tied to the frame. You then just plug the hole on the frame. Job done.

If you really want to get complicated about it then you can buy a very nice catch tank that sits in the semicircle of the swingarm and you can thread all your carb tubes into it too.

The reason the engine vents into the frame is that there is a regulatory requirement for what they call a closed loop ventilation circuit to prevent oil spilling out in a crash. If you don't use a closed loop, then the racing regulations state the use of a catch tank.

With regards to the two vents on the valve cover, they were added because there were concerns, particularly on the 650, about build up of crank case pressure when there was a single vent and demanding operating conditions . In my experience, however, this is not an issue until you're beyond the 65 horsepower mark and therefore in most cases it's not worth worrying about really.

Hope this helps,
Simon

well i think i'll remove the camchain one (in this way my alu tank will fit properly) and let the other one plugged in to the frame or let it flows into the catch can.. which solution is better?

Pastullo,check my gallery to see what I have done.I tried to made the same system with the factory Bergs.As jocke_D said is the choice of the factory!

Regards sotosberg

With regards to the two vents on the valve cover, they were added because there were concerns, particularly on the 650, about build up of crank case pressure when there was a single vent and demanding operating conditions . In my experience, however, this is not an issue until you're beyond the 65 horsepower mark and therefore in most cases it's not worth worrying about really.

Hope this helps,
Simon[/quote]

I would say that there might of been extra lubrication in mind here to get at the cam and valve train, the oil is thrown up the tube that lies above the cam chain sprocket and runs down the one over the valve train.
If it was just crank case pressure they were worried about why not put the vent at the front of the engine where it is less likely to pull oil up and into the air box.
Has any one started the engine without the pipe connected to the rocker lid?, I once did don't have to say what came out, but there was loads of it.

Regards

Sparks.