CNW '72 Breather Mod

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rvrich - appreciate the post but still have no clue what a transmission layshaft has to do with crankcase breather. :?:

All other posters - greatly appreciate the feedback and info about direct experience. :D

i have tried the generic solutions and had little success with them. A commando-specific solution to a real issue has great appeal to me.
Especially one from an honest and competent supplier such as CNW /JCE.

Yes, it will cost more up-front. But I am convinced that it will cost less and be more reliable in the long run.
AND I hope to have a 'long run' with this fine machine.
Looking forward to installing the Jim Comstock/CNW 1972 Combat crankcase breather!
 
My experience is that with a XS650 breather, it used to effectively get blocked with emulsified oil. Mine was mounted up just behind the carburettors.

I have one of Jims "large sump plug" type on now which of course has eliminated the emulsified oil problem. It works very well with all of the benefits already mentioned and I'm very pleased with it. On dismantling it this year, I did find that one of the reed valves (unless it was both....can't remember) had turned on the screw mounting very slightly leaving a very small ? 1mm gap straight past the valve (on one side towards the bottom of the long edge), although I don't suppose it made any real difference as to how well it worked. Easily resolved, by loosening the screws on the reed valves and moving them back to perfectly "square."

tomspro wrote;
Yes, it will cost more up-front. But I am convinced that it will cost less and be more reliable in the long run.
Click to expand...
I totally agree. 8)
 
Gee, now I feel like I am beating a dead horse. Tomspro, do you know whether or not your layshaft bearing has ever been changed from the factory bearing? If you do not know, then you should read up on layshaft bearings. Trust me, if you are tearing down the transmission to install a new layshaft bearing, then make the breather job easy on yourself by doing them at the same time.

All that other shite about doing the job in a fashion that doesn't cause you to hate your bike is probably rubbish.

Russ

PS-It doesn't surprise me to be in the minority. I usually am. Or more likely facing the corner with a dunce cap on my head!
 
comnoz said:
illf8ed said:
I'm using the XS650 reed valve (as are others on this site) with the stock breather hose going to this unit under the seat then normal hose from the reed valve box to the top of the oil tank on my '72 combat engine. I have no experience Jim's breather. Are there value benefits at a much higher cost of $220/per?
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1.First my breather does not plug up with oil water mix from condensation. It is attached to the engine so it runs at engine temperature and gathers no condensation.

2.My breather is closely coupled to the crankcase so the reeds resonate with the crankcase pulses. That means it will still create a vacuum even at highway speed.

3.My breather picks up low in the engine case so it removes excess oil that has gathered in the cases when parked. It will clear a wet sump condition in only a few slow kicks or a few seconds after the engine is started.

4.It's out of sight and out of mind. Jim
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+1 on what Jim stated here. Especially comment 1.
I used a spare 73 850 engine to keep on riding…you know keep on keeping on…I don’t want a pickle I just want to ride my motorsickle. 8)
I have used the XS type reed valve on my 850 interstate and found water mix and condensate in my engine oil tank. :shock: The 73 engine was used as an interim engine on my 74 interstate during the rebuild. I switched out this engine back to my original 74 850 engine when the rebuild was complete. I installed Jim’s unit by doing my own machining. But that is just me. If you don’t have machining skills then ship it out and get it done right. I used the XS reed valve up high inside the battery compartment and found that it was too far from the engine to work properly. mistake. :? This caused the oil water to congregate inside the bottom of the oil tank. Not good. The reed valve must be on the engine as per the CNW/Comstock design or the one Ludwig cooked up. Keep them real close to make it work. Since I have installed the comnoz designed breather I couldn’t be happier.
From my observations and two cents worth.
Cheers,
Thomas
CNN
 
That is great to know that your now happy with "reed Valve" .. Your story/message indicate that you previously ingested H2O causing problems and could not eliminate it... Can you please tell me/us what your normal riding conditions are eg, daily temp and whether snowing raining or just very wet all the time... So that i and others can realisticy compare your info with our own experiences
Your in Canada but the daily temps can vary as they do here (Aust) from place to place by 50c ...

To me, interesting that when valve is place very close to sump it seemingly works better in your "cooler" ??????? conditions....

Thinking outloud here but "Maybe the engine needs a shroud to increase engines ambient temp to evaporate induce moisture if riding in continuously wet conditions" Just tinkin...
 
It's possible the rebuilt engine isn't pumping as many ignition gases into the cases and that is why it isn't frothing.

You know something guys. I am kinda surprised by something here. The original poster isn't asking whether or not to install the reed valve. He is asking whether or not it can be done with the engine in the frame. Presumably with the transmission in situ. This is why I keep asking about the layshaft bearing. What I am really going for here is to take the transmission out of the bike while he is reburbishing stuff, so that he can go through the transmission. Then the breather is a piece of cake. What surprises me, I guess, is that nobody else here would recommend he go through the transmission before he gets his bike on the road!

FWIW, he bought the breather. So we just need to make him feel better about all the money he is spending.

Oh, and while you have it torn down that far, do your isolastics and put Kegler clamps on the swingarm, and...
 
rvich said:
It's possible the rebuilt engine isn't pumping as many ignition gases into the cases and that is why it isn't frothing.

You know something guys. I am kinda surprised by something here. The original poster isn't asking whether or not to install the reed valve. He is asking whether or not it can be done with the engine in the frame. Presumably with the transmission in situ. This is why I keep asking about the layshaft bearing. What I am really going for here is to take the transmission out of the bike while he is reburbishing stuff, so that he can go through the transmission. Then the breather is a piece of cake. What surprises me, I guess, is that nobody else here would recommend he go through the transmission before he gets his bike on the road!

FWIW, he bought the breather. So we just need to make him feel better about all the money he is spending.

Oh, and while you have it torn down that far, do your isolastics and put Kegler clamps on the swingarm, and...
Click to expand...

Remove transmission, layshaft bearing, new Isolastics, swingarm, .... enough already!!! [runs screaming to the nearest Honda dealer] :oops:
 
tomspro said:
rvich said:
It's possible the rebuilt engine isn't pumping as many ignition gases into the cases and that is why it isn't frothing.

You know something guys. I am kinda surprised by something here. The original poster isn't asking whether or not to install the reed valve. He is asking whether or not it can be done with the engine in the frame. Presumably with the transmission in situ. This is why I keep asking about the layshaft bearing. What I am really going for here is to take the transmission out of the bike while he is reburbishing stuff, so that he can go through the transmission. Then the breather is a piece of cake. What surprises me, I guess, is that nobody else here would recommend he go through the transmission before he gets his bike on the road!

FWIW, he bought the breather. So we just need to make him feel better about all the money he is spending.

Oh, and while you have it torn down that far, do your isolastics and put Kegler clamps on the swingarm, and...
Click to expand...

Remove transmission, layshaft bearing, new Isolastics, swingarm, .... enough already!!! [runs screaming to the nearest Honda dealer] :oops:
Click to expand...

Wow... Your nearest Honda dealer stocks Norton layshaft bearings and isolastics...? Cool...!
 
olChris said:
That is great to know that your now happy with "reed Valve" .. Your story/message indicate that you previously ingested H2O causing problems and could not eliminate it... Can you please tell me/us what your normal riding conditions are eg, daily temp and whether snowing raining or just very wet all the time... So that i and others can realisticy compare your info with our own experiences
Your in Canada but the daily temps can vary as they do here (Aust) from place to place by 50c ...

To me, interesting that when valve is place very close to sump it seemingly works better in your "cooler" ??????? conditions....

Thinking outloud here but "Maybe the engine needs a shroud to increase engines ambient temp to evaporate induce moisture if riding in continuously wet conditions" Just tinkin...
Click to expand...

My normal riding habits consisted of two-hour blasts on weekdays in good weather. 70-90 F during summer. I will do 200 miles or more for trips or events. I normally do not drive in the rain if I can help it, as I don’t like cleaning my bike back to bright chrome. Too much work and I would rather be riding. I put lots of mileage on my bike per year and I usually drive till the snow flies or how much my fingers can tolerate the cold. What I did find with the XS reed valve is that it never really cured the oil seep from the tach housing. Even when I mounted it at the spigot coming out of the back of the timing case. But the Comstock design did.
Cheers,
Thomas
CNN
 
CanukNortonNut said:
My normal riding habits consisted of two-hour blasts on weekdays in good weather. 70-90 F during summer. I will do 200 miles or more for trips or events. I normally do not drive in the rain if I can help it, as I don’t like cleaning my bike back to bright chrome. Too much work and I would rather be riding. I put lots of mileage on my bike per year and I usually drive till the snow flies or how much my fingers can tolerate the cold. What I did find with the XS reed valve is that it never really cured the oil seep from the tach housing. Even when I mounted it at the spigot coming out of the back of the timing case. But the Comstock design did.
Cheers,
Thomas
CNN
Click to expand...
Excellent news! I am looking forward to installing the Comstock breather on my machine.

Just removed the original breather. A couple of large screens in there. Certainly nothing to deal with crankcase pressure / vacuum.
And the plastic valve I put on top of the breather hose two months ago is already worthless - can blow thru both ways.
 
And the plastic valve I put on top of the breather hose two months ago is already worthless - can blow thru both ways.
Click to expand...

If you are referring to the Dorman brake booster check valve, I believe you'll find it is little more than a placebo. Makes you feel good when you first install it. Later you'll find your Norton still leaks oil in the same places. Placebos are cheap, real reed valve breathers cost a bit more.
 
I've not noticed a problem with mine. When the engine fires up it just puts any oil in the line back into the oil tank. I'm no expert on this subject but I can tell you this. I had some dripping from the front of my engine in the rocker tube area and the moment I installed this valve the oil leak stopped....Phillyskip
 
Fast Eddie said:
tomspro said:
rvich said:
It's possible the rebuilt engine isn't pumping as many ignition gases into the cases and that is why it isn't frothing.

You know something guys. I am kinda surprised by something here. The original poster isn't asking whether or not to install the reed valve. He is asking whether or not it can be done with the engine in the frame. Presumably with the transmission in situ. This is why I keep asking about the layshaft bearing. What I am really going for here is to take the transmission out of the bike while he is reburbishing stuff, so that he can go through the transmission. Then the breather is a piece of cake. What surprises me, I guess, is that nobody else here would recommend he go through the transmission before he gets his bike on the road!

FWIW, he bought the breather. So we just need to make him feel better about all the money he is spending.

Oh, and while you have it torn down that far, do your isolastics and put Kegler clamps on the swingarm, and...
Click to expand...

Remove transmission, layshaft bearing, new Isolastics, swingarm, .... enough already!!! [runs screaming to the nearest Honda dealer] :oops:
Click to expand...

Wow... Your nearest Honda dealer stocks Norton layshaft bearings and isolastics...? Cool...!
Click to expand...



I like this guy........... :p
 
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