So is the blown/sucked-out base gasket a result of my modifications to the Hayden KrankVent?

Only da shadow knows.  

DBM,
Got my Krank Vent today. Looks a lot like yours.
One thing I noticed, the package says that it allows a little air to go back into the crankcase. That would limit the amount of vacuum in the bottom end. Your mod (different umbrella valve) made for a tighter seal, and I'm assuming, more crankcase vacuum.
And yours sucked the base gasket in.
So, maybe you overdid it?
Thoughts?

On 10/30/19 DBM wrote:

"So is the blown/sucked-out base gasket a result of my modifications to the Hayden KrankVent?  Only da shadow knows."

Yes Armen, there's a chance I overdid it.  The mystery is the amount of vacuum I measured when I was testing it.  It was pretty miniscule.  The most I could pull, even with the leak patched up, was 1" Hg.  I'm pretty sure I can get the gaskets and seals to hold 1" Hg.  But I don't know how much vacuum it pulls under normal riding conditions.  What does it do at WOT around 7K?  What does it do when compression braking?  What does it do when I load it up at low rpm?

So the plan is to get a good, solid base gasket installed (i.e. copper) and try again.  I will instrument the crankcase and go for a ride.  Then we will know just how much vacuum the thing can pull.  The Harley umbrella valves seal 100% at rest, they don't have a gap.  Other motorcycles use reed valves.  I don't see any reason why this thing shouldn't be able to hack it.

If the thing pulls too much vacuum, and gaskets are simply not up to the job (the only one left is alternator cover), then I will incorporate a bypass bleed orifice, or a relief valve (vacuum breaker) like Versy mentioned.  If that doesn't work, then I will take the contraption off.  It will have been an interesting project.

Hey Armen, can you post some pics of the Hyaden so we can compare to what I received?  Is it loose and wiggly?    

I predict even with the copper gasket ,an oil leak will in time appear in the came location, if  run at rpms between 7000 and 7500 .

Armen, are you saying that you took your brand new Hayden KrankVent and installed it on your friends MotoGuzzi?  You really are a sweetie.  

What's the displacement on that G11?  What is the angle between cylinders? What sort of redline?  Please let us know how it works out.  Wait a minute, its like 30 below over there right now.  Will we have to wait five months to find out?

More and more, I'm valuing the Savage as an ICE primmer/teaching mechanism.   The faster I want to go, the more I gotta know; what I don't know is without bounds... so, perhaps, is the potential for learning- and performance improvements.  

Prior to owning this machine, my understanding of ICE's was limited to Fuel, Air, Spark, and Fire- so when a performance need imposes, my ignorance supplies a vacuum, quickly filled with stuff I don't yet understand.   Bits of erudition and arcane knowledge are forced past my filter.   This may be tedious to witness, and taxing of patience- so thanks for your charity, in advance-

Please, disabuse me if this understanding is wrong:

The Savage airbox has been designed to do double-duty, both supplying air to the carb, and acting as a breathing receptacle for the crankcase.   That crankcase respiration introduces aerosolized/atomized oil into the breather box, where it soaks the air filter and is inhaled by the carb; this is a performance killer, restricting airflow and overly enriching the mix at high RPM's.

DBM said 'to-hell-with-that', plugged the crank case breather inlet to the airbox, routing the hose instead to a new organ to support the requisite crank case respiration; this new organ consists of a chamber with a filter top, a drain bottom, and a crank case vent tube inlet at a section of chamber filled with steal padding to obstruct the free passage of aerosolized oil up the chamber to the filter.   Happy-day! -the engine breaths/performs better, and the airbox filter requires less attention.

This spawns more than a few questions-

1] It's been suggested elsewhere that such an auxilory crank breather might reduce oil consumption. How can that be?

2] Is there some reason the oil collected in the auxiliary crank case breather shouldn't be reintroduced to the crank case?

3] I'll likely ditch the stock speedo cable after replacing the fuel tank; might I use the freed crank case speedo orifice as a return for oil collected in an auxiliary crank case breather?

4] Don't some folks dispensed with the breather box?  What are the implications for the crank case breather tube in such a system?  Digressing, does any new air intake for the carb need to be contrived in such a way as maintain a degree of pressure or avoid vacuum?   I saw one Savage with a forward-facing carb air port feeding the carb via a J tube, supplying air at increasing speed and pressure; is that nuts?

5] What didn't I ask that I should have?

This looks like as good a time as any to update this post.

Mavigogun, the stock breather setup connects the engine breather to the airbox cavity located between the air filter and the carburetor inlet.  Since ALL air filter elements have some degree of inherent restriction, the cavity between the filter and the carburetor inlet will operate slightly below atmospheric pressure.  This low pressure (depression) increases (i.e gets even lower) as the engine speed increases.  That's not a big deal at moderate speeds, but when you start operating at higher speeds, the increased depression starts to act in concert with the increased crankcase pressure to transfer oil mist out of the engine into the airbox.  

The filter restriction remains constant but the airflow increases, so the depression in the airbox increases.  Blowby past the rings increases with load and rpm so crankcase pressure increases.  It's the perfect storm.  Higher pressure in the crankcase working with lower pressure in the airbox equals higher differential which results in increased vapor/mist flow.

Since I installed the dedicated breather/catch can, I have not found one single drop of oil in the can.  Not even a film of oil.  I don't pamper my motorcycle, I ride it hard and put it to bed wet.  No oil in the catch can, zero, nada, well over 1000 miles.

I believe HotRod also posted that he is running an open breather line and never gets any oil out of it.

When I first disconnected the breather hose to test this concept, I ended up with oil all over the side of my bike.  That was all the residual slop left over in the head cover screen, breather cavity, hose, etc.  Once that was all purged, zero oil comes out of my breather.  That's after at least 1000 miles.

It's simple enough to test.  Just pick up a small breather filter and try it out.  I think you will like it.  

The failed cylinder base gasket seems to be the result of inadequate cylinder stud stress, not excess pressure or vacuum in the crankcase.  This old post provides all the specifics.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1576269113/12#12

Quote:


Suzuki's design intent was to be able to sell the motorcycle. It's been illegal for the manufacturers of ICE vehicles to vent crankcase emissions into the atmosphere for a pretty long while.
They all have to deal with that issue somehow. The simplest method is to route the blowby back into the intake where it can be burned.