Which reed valve breather?

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Fast Eddie

Fast Eddie

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Chaps,

I have used the Comnoz sump plug type reed valve breather on my 850 and have been very pleased with its performance.

The Maney engine I’m building already has the machining on the rear of the case to take the cNw type.

I’ve got both on the shelf, both are made by Comnoz and both look excellent, and can’t decide which to use.

Advantage of the sump plug type is there’s less chance of interference when fitting / removing the gearbox.

Is there any advantage to the case mounted type? Has anyone compared the functionality of both?
 
gtiller said:
The sump plug type is superb for evacuating a wet-sumped case.

Because of the tilty engine angle, the rear mounted option will not be quite as effective.
Click to expand...

i agree with your statement however it is really suppose to act as a one way breather, evacuating the sump oil is a secondary benefit, and thus i prefer the rear mount option...
 
Yeah, the sump emptying quality may be a secondary bennefit... but it’s a bloody handy one with a Norton!

If the case mounted breather has no bennefit over the sump mounted one, then this one bennefit, however secondary, is enough to swing the decision... for me anyway.
 
Actually the rear mounted breather evacuates the oil the same as the sump plug breather.

Between the sump plug breather and the combat style breather -like used on the Maney case -there is little if any difference in it's effectiveness.

If the case is machined for the rear mount breather without the combat case adapter, then the breather has a little more volume and will evacuate the case a little faster. But the end result is the same.

So basically the only difference is the sump breather is easier to install, and the rear case breather is out of sight and does not need to be removed for service.

The rear mount breather is also not the lowest point on the bike when your loading a trailer as the sump plug breather will be. Jim
 
Thanks Jim.

One more question with the case mounted breather, does it matter if it’s mounted with the hose routed up and over, or down and under ?
 
gtiller said:
The sump plug type is superb for evacuating a wet-sumped case.

Because of the tilty engine angle, the rear mounted option will not be quite as effective.
Click to expand...


Did you read the comment by comnoz? I think a retraction is in order.

Comnoz quote:

“Actually the rear mounted breather evacuates the oil the same as the sump plug breather.

Between the sump plug breather and the combat style breather -like used on the Maney case -there is little if any differencein it's effectiveness.”
 
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Although I suspect JimC forgot to take his angry pills this morning he has a point.
When a forum member makes a comment that subsequently is proven be wrong (me included} I believe it would be good form to edit their post to reflect that the comment is inaccurate.
Would stop a potential trap for future "searchers".
Smile a bit more though Jim - seriously! The apparent anger in your recent posts can't be good for you.
Cheers
Rob
 
The difference between

the rear mounted breather evacuates the oil the same as the sump plug breather

&

the rear mounted option will not be quite as effective

Is hardly justification for WW3, just a gentle nudge would have been enough.

Chill out its nearly Xmas.
 
robs ss said:
Although I suspect JimC forgot to take his angry pills this morning he has a point.
When a forum member makes a comment that subsequently is proven be wrong (me included} I believe it would be good form to edit their post to reflect that the comment is inaccurate.
Would stop a potential trap for future "searchers".
Smile a bit more though Jim - seriously! The apparent anger in your recent posts can't be good for you.
Cheers
Rob
Click to expand...


It’s not anger in my posts, it’s total disdain for bullshit statements. There has been a rash of uncredible posts lately. I have no time for those who make unsupported, inaccurate claims. Opinions, yes.

I have been a forum member for over 11 years. There has been a marked degradation of credible information posted on this forum over the years. Not everyone is able to separate the wheat from the chaff. So, I think it is incumbent upon those who know better to point out these uncredible, unsubstantiated claims. I don’t claim to be a Norton expert, but being an old farm boy I can spot bullshit when I see it. :)
 
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To those who cannot take criticism when they make false statements I suggest they tie kerosene soaked rags around their ankles so the ants don’t eat their candy ass. :D
 
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@JimC you've made your point, please don't be vulgar.

...also with 11 years experience of this superb forum, I am surprised to see that you are not a VIP member - contributing toward the cost of running it.
 
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