One way reed valve breather...does it really make a difference?

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André Bourbonnais

André Bourbonnais

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I'm restoring a 72 Commando and no mods have been made. I'm reading up on a one way reed breather and noticed it's a simple install with no machining required.

Yay or nay? Do you use them and is it worth it?
 
André Bourbonnais said:
I'm restoring a 72 Commando and no mods have been made. I'm reading up on a one way reed breather and noticed it's a simple install with no machining required.

Yay or nay? Do you use them and is it worth it?
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Have a Comstock reed breather on all 3 of my Nortons. Definite yay
 
Will a reed breather improve an engine that doesn't leak oil and doesn't wet sump?( 2 month sit, no problem)
I realize this is a bit of a rarity for a Commando.

Glen
 
Maybe I've been at the Koolaid for too long, but I thought it was pretty well established that creating a vacuum inside the crankcase was beneficial.

Here are a list of the things I believe to be true:
1.) The good weather will last forever
2.) All breasts are real
3.) The Comnoz breather is one of the best mods for our Commandos.

Without the reed, the breather is basically a Jake Brake.
 
Yes it will as the movement of air in and out of the tank is much reduced so less likely for excessive oil to be pushed into the airfilter, plus you may be leak free now but ?
 
I've got Comstock sump breathers on both of my Commandos. Would do it again in a heartbeat.
 
I wonder if it is more effective on pre MK3 Commandos, you know, the ones that leak oil;)
Seriously, the damn thing has never leaked a drop, even after a hard mountain run on a hot day.
I park it in the modern bike part of the shop, along with the 1360 Vincent, also dusty dry.

The rest of the shameful crew straddle incontinence trays. Some of them could use a reed valve or two.

Glen
 
Yup , my Norton doesn't mark it's territory either , never has .... is that the only reason to fit a reed valve though ?
 
The reed on the right is made in Germany by BMW. The reed on the left is made in China/Taiwan. I chose to use the BMW reed because its clean/tidy and does not require holes to be drilled into the case. Reed breathers are the way to go - I started using them in the mid 1980s when dragster Leo Goff showed me how.

One way reed valve breather...does it really make a difference?
 
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The Comstock ones have the benefit of being low down and therefore ideal for quickly emptying wet sump back to th correct level.

The benefit to the sump plug one is that it is simply a screw in job.
 
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