Product release - new style one way case breather

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jseng1 said:
This new one way breather fits inside the timing cover so you don’t have to drill holes in the exterior of your cases (potential leaks near the rear tire). For 850s you retain the original breather to the oil tank. For 750s you plug the original cam vent and transfer the elbow fitting to the mag blank plate and plumb it to the oil tank.
Click to expand...

I see this solution as DEFINITELY more involved on installation than the one that bolts to the back of the timing chest. This one must have the engine totally apart to install, the other one just needs the timing cover removed to install (unless you have the bolt-on plate).

Second issue is there are some models that have neither the 74/75 screwed-in breather pipe nor the early style bolted-on plate.
 
grandpaul said:
jseng1 said:
This new one way breather fits inside the timing cover so you don’t have to drill holes in the exterior of your cases (potential leaks near the rear tire). For 850s you retain the original breather to the oil tank. For 750s you plug the original cam vent and transfer the elbow fitting to the mag blank plate and plumb it to the oil tank.
Click to expand...

I see this solution as DEFINITELY more involved on installation than the one that bolts to the back of the timing chest. This one must have the engine totally apart to install, the other one just needs the timing cover removed to install (unless you have the bolt-on plate).

Second issue is there are some models that have neither the 74/75 screwed-in breather pipe nor the early style bolted-on plate.
Click to expand...

The easiest is the Yamaha 650 breather from Mikes XS - just splice it in the hose to the oil tank. Then there is yours which goes outside the old magneto location which is nice. But plugging the vents in the timing chest makes the one way valve work more efficiently and is best for eliminating leaks.

The one way valve hasn't been available in the timing chest before. When the idea came to me in the middle of the night I knew it had to be done. It just took awhile to get it right. Adapting a pipe threaded hose elbow or an original cam vent elbow to the old magneto location should be easy enough. Please describe which model and the layout you are talking about.
 
grandpaul said:
Second issue is there are some models that have neither the 74/75 screwed-in breather pipe nor the early style bolted-on plate.
Click to expand...

Which models are those, Paul? I thought all the ones with the rotary breather on the cam, and the '72s with the infamous breather on the bottom of the case, still had the bolted-on-plate. And all the '73 and on engines I've seen had the screw-in breather stub. Were there some sort of transition models in '72/'73 that were different?

Ken
 
Yep, I have a 1972 Combat engine - 206626

You can see there is no machining or bolted-on plates
 

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I'm no doubt missing something here, but I cant see what is stopping the motor breathing through the main bearings, so I don't understand how a vacuum could exist within the crankcase?
 
Clanger said:
I'm no doubt missing something here, but I cant see what is stopping the motor breathing through the main bearings, so I don't understand how a vacuum could exist within the crankcase?
Click to expand...
The primary side has a proper seal, and the timing side has a "quasi" seal with the dished disc behind the worm gear on the crank.

You'll never get a significant "vacuum" (as has been exhaustively studied), but you WILL reduce crankcase PRESSURE on the piston downstroke; that is where the oil weeping is stimulated.
 
jseng1 said:
The easiest is the Yamaha 650 breather from Mikes XS - just splice it in the hose to the oil tank. Then there is yours which goes outside the old magneto location which is nice.
Click to expand...
Agreed


jseng1 said:
But plugging the vents in the timing chest makes the one way valve work more efficiently and is best for eliminating leaks.
Click to expand...
"More efficiently" is a relative term. I'd rather not mess with the original oiling scheme. End result is effective case pressure reduction, that's the bottom line.
 
grandpaul said:
Clanger said:
I'm no doubt missing something here, but I cant see what is stopping the motor breathing through the main bearings, so I don't understand how a vacuum could exist within the crankcase?
Click to expand...
The primary side has a proper seal, and the timing side has a "quasi" seal with the dished disc behind the worm gear on the crank.

You'll never get a significant "vacuum" (as has been exhaustively studied), but you WILL reduce crankcase PRESSURE on the piston downstroke; that is where the oil weeping is stimulated.
Click to expand...

Well, that's more or less what I thought, and I'm glad there is some general breathing in the plan as I was wonderin how this will all affect the lubrication of the chains, I assume that testing has come up with the answer ' not much'?.
 
Clanger said:
grandpaul said:
Clanger said:
I'm no doubt missing something here, but I cant see what is stopping the motor breathing through the main bearings, so I don't understand how a vacuum could exist within the crankcase?
Click to expand...
The primary side has a proper seal, and the timing side has a "quasi" seal with the dished disc behind the worm gear on the crank.

You'll never get a significant "vacuum" (as has been exhaustively studied), but you WILL reduce crankcase PRESSURE on the piston downstroke; that is where the oil weeping is stimulated.
Click to expand...

Well, that's more or less what I thought, and I'm glad there is some general breathing in the plan as I was wonderin how this will all affect the lubrication of the chains, I assume that testing has come up with the answer ' not much'?.
Click to expand...

There is plenty of oil in the timing chest to be picked up by the oil pump worm gears and thrown to the cam chain and distributed/splashed all over the place. Even with the new oil drain return at the bottom the oil level is more than high enough. There is actually too much oil in the timing chest withe the stock setup and that is why the lower hole is added. The oil level doesn't drop all the way down to the new lower oil return hole - it drains as fast as its able to but the level stays higher than the drain hole. If you're worried about it you can leave the original high oil return hole (don't plug it) and not add the new lower one and let the chains and gears churn up all that extra oil for no reason (the one way valve will work the same). All these details have already been beaten to death in an earlier one way breather thread that went on and on (the oil level was observed). And yes - this setup has been tested and it works perfectly.
 
What about the early 20M3S with the camshaft breather that doesn't have the timing case breather nor the bolt on plate where the mag went. Or did I miss that one? I suppose a breather tube would have to be added to the timing chest somewhere? Like the second picture on http://atlanticgreen.com/engcases.htm. It also all means the engine has to come apart for installation. But if I did anything, that's the case anyhow. This was all pretty new and confusing to me when I rebuilt mine so I stuck with the original setup.
 
Product release - new style one way case breather


I sent these down to Norman White today , he will give them the onceover . Cam shaft breather cases. so we will
fit a breather in the case half and see how it goes from there.!

Jg
 
jseng1 said:
All these details have already been beaten to death in an earlier one way breather thread that went on and on (the oil level was observed). And yes - this setup has been tested and it works perfectly.
Click to expand...

Sorry for asking, if it's been beaten to death, I'm just a casual reader and dont read every post, just trying to get my head round your product, thats all...
 
dogT - for rare 750 cases that don't have a mag plate I will send out a pipe/hose elbow fitting as below - just put some pipe threads where the mag plate would be (or use a cam elbow fitting). It will also work for magneto motors by installing the hose fitting on the outside of the timing cover (opposite the magneto).

Product release - new style one way case breather


auldblue - I decided to lower the price and will refund the difference to customers who just ordered.

clanger - that old post that has already "beaten to death" this subject is years old and I realize I'm stepping into it all over again. The vacuum mentioned is small - think of it as a positive with each downstroke and then a negative pulsation with each upstroke. The valve reduces the positive side and increases the negative side - give you a net overall pressure close to zero and reducing leaks. The drain hole is generally full of oil - that and the restrictor plate at the main bearing helps seal off the timing chest. There's many ways to look at this but as Grand Paul said "the bottom line is that pressure is reduced" - the proof is in the video on the 1st page of this thread.
 
I made some tests to make sure there wasn't any problem with oil draining from the head to the timing chest. Here's the vid:

[video]https://youtu.be/y3TZlr869Fc[/video]

Even so, I've decided that it would be best to put some more time/testing on this idea and wait for some feedback before sending out any more.
 
My thoughts are that if the engine has excessive blow by from worn bores rings or guides that may make matters worse in respect of oil drainage. As the valve would be having to deal with more volume of gasses. These engines are capable of still running quite well when internally they are in a very poor state (well mine was) an am guessing Jim's test bike is not like that. More that sometimes the parts fitted can't work because the things they are fitted to are not working as they should be.
 
toppy said:
My thoughts are that if the engine has excessive blow by from worn bores rings or guides that may make matters worse in respect of oil drainage. As the valve would be having to deal with more volume of gasses. These engines are capable of still running quite well when internally they are in a very poor state (well mine was) an am guessing Jim's test bike is not like that. More that sometimes the parts fitted can't work because the things they are fitted to are not working as they should be.
Click to expand...

Yes you are right but it also it depends on how the motor is set up. It works fine in my test bike. But I've learned that a motor that is set up different can change things.

The pressure in the sump is reduced by the reed valve and you must have the correct balance of air pressure between the sump and the timing chest. This balance is what can change from motor to motor depending on the setup and the balance cannot be too far off.

It’s a clean design but I’m not going to send any more out until I know it works for every variation. I know how it could be redesigned to work for everyone but then it may become too expensive and time consuming.
 
I do like the idea of it an the design of it Jim for the record. An if you are the type of owner that wants their machine to look as the factory built it (am not) regardless of benefits of alterations this may be an answer to the issue of pressurising the motor. But owners must release (though some never do) if the motor has bigger issues they must address them (even if that means removing the original manufacturer's part that is now worn out).
 
toppy said:
..if you are the type of owner that wants their machine to look as the factory built it (am not) regardless of benefits of alterations this may be an answer to the issue of pressurising the motor.
Click to expand...
There are only a few places where a reed valve can be installed and not be seen - all would be within the existing breather plumbing.
 
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