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breather pipes?

bestbyet
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Joined: Tue Oct 21, 2003 6:53 am

breather pipes?

Post by bestbyet » Sat May 22, 2004 4:28 am

there are two pipe outlets in cylinder head just below carbs any one know what they are for???

mrfirebird
honda305.com Member
Posts: 16
Joined: Sun May 02, 2004 9:13 pm

Re: breather pipes?

Post by mrfirebird » Fri Jun 18, 2004 2:17 pm

if there small tube there is a Y tubing that goes from the block to the right side air filter.don't know what it does,sorry.

87we4turbo
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Joined: Sat Nov 29, 2003 7:48 am

Re: breather pipes?

Post by 87we4turbo » Mon Jun 28, 2004 9:38 pm

bestbyet wrote:<br />there are two pipe outlets in cylinder head just below carbs any one know what they are for???<br />
<br />I know it's been a while since your post, but here goes. Those are vents for the intake valve guides. It was explained to me many years ago that their purpose is to prevent oil from being sucked down the guides to reduce oil consumption.<br />John

emacklin
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Joined: Wed Dec 22, 2004 5:17 pm

Re: breather pipes?

Post by emacklin » Tue Aug 30, 2005 6:54 pm

bestbyet wrote:<br />there are two pipe outlets in cylinder head just below carbs any one know what they are for???<br />
<br /><br />Don't know, but mine were blowing oil out like a banshee.<br /><br />It came out clean, but enough to go through 4 or 5 quarts over 1600 miles.<br /><br />If anyone has any info on these, I'd love to hear it too.

kustommusic
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Joined: Sat Sep 11, 2004 6:44 pm
Location: Goshen Indiana

Re: breather pipes?

Post by kustommusic » Wed Aug 31, 2005 7:10 pm

The two small nipples that are by the carbs on a cb77 are vaccum ports for tuning purposes.The breather tube is on the valve cover on top of the cylinders and goes from the top to under the crankcase cover. Any &quot;Y&quot; tube going to the air cleaner is a engine breather or carb overflow. Which bike had this? Steev Greer

LOUD MOUSE
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Location: KERRVILLE, TEXAS

Re: breather pipes?

Post by LOUD MOUSE » Thu Sep 01, 2005 11:33 am

The vents between the carbs (CA/CB/CL72/77 HONDAS) were ment to remove any moisture at the intake valve guides. The tubes went to a plastic &quot;Y&quot; and then to the front of the right side air cleaner. Nothing to do with engine tuning. They were so important and useful that HONDA discontinued them with the 1967 engines. If oil is coming fron the tube I'd identify which one (or both) and look for a cracked valve guide. If oil is coming from the top vent I would suspect the top gaskets are missing or installed backwards or at the worst bad or broken rings. The rings can be proven with a compression test. .................
RIDE IT DON'T HIDE IT!

kustommusic
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Posts: 585
Joined: Sat Sep 11, 2004 6:44 pm
Location: Goshen Indiana

Re: breather pipes?

Post by kustommusic » Thu Sep 01, 2005 4:42 pm

O thrash me with a greasy chain!! I thought the nipples were the same as my Yamaha triple. Those are vac ports for tuning. My mistake I assumed the honda was the same.Thanx for the correction loud mouse,don't need any misinformation, things are hard enough! Steve greer

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