81 CV carb vent TEEs

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old gringo
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81 CV carb vent TEEs

Postby old gringo » Thu Jun 19, 2008 6:21 pm

Got a remanufactured set of carbs. My question concerns the vent TEEs between 1&2 and 3&4. is there supposed to be any hoses attached to the T other than the connecting hoses, or doe's the end of the hose simply point in the air without a hose attached?
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cb650
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Re: 81 CV carb vent TEEs

Postby cb650 » Thu Jun 19, 2008 8:36 pm

They each have a hose that goes into another T then to the airbox.
Did you clean the tank out?!?!?!?!

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Buber
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Re: 81 CV carb vent TEEs

Postby Buber » Fri Jun 20, 2008 1:20 pm

I had problem once with those T's. They were cracked/blocked and carbs were overflowing.After some fiddling I put 4 separate vinyl pipes there that went behind and under the carbs, and problem was gone.... :D

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old gringo
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Re: 81 CV carb vent TEEs

Postby old gringo » Fri Jun 20, 2008 9:53 pm

Well, don't have any more Ts, so I'll just run 2 hoses from them out of the way. :wink:
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Chris
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Re: 81 CV carb vent TEEs

Postby Chris » Wed Jul 23, 2008 9:27 am

You might get better fuel mileage with the vent going into the air box instead of the atmosphere. I don't know if you're concerned about that, but it was just a thought.
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5.4L to Freedom
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Re: 81 CV carb vent TEEs

Postby 5.4L to Freedom » Wed Jul 23, 2008 9:42 am

In the diagram of the carbs i posted in the 3way fuel t post, could you tell me the part number of the vent t's?
Dr. SOHC650... former rider I got sick of fixin my CB so I bought a Harley and fix everyone elses...

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Chris
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Re: 81 CV carb vent TEEs

Postby Chris » Wed Jul 23, 2008 4:39 pm

Um, looks like the same part to me. Let's see what old gringo says.
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old gringo
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Re: 81 CV carb vent TEEs

Postby old gringo » Wed Jul 23, 2008 8:13 pm

The only reason I have the T's installed is that they came with the re-manufactured carbs. Otherwise, I don't think they are really necessary except for the straight tube between 2&3. My old set didn't have 'em.
Not sure about the difference in gas mileage but as they just keep the carb
pistons from creating a suction that would flood the airbox I wouldn't worry about them unless you find a good price. Bike Bandit parts are:
218615-001 @ 39.35
218879-001 @ 39.35 :shock:
BTW my fuel mileage is currently 60 mpg if I baby it and 55 mpg if I ride normally :lol: :lol:
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Buber
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Re: 81 CV carb vent TEEs

Postby Buber » Thu Jul 24, 2008 3:19 am

Chris wrote:You might get better fuel mileage with the vent going into the air box instead of the atmosphere. I don't know if you're concerned about that, but it was just a thought.

Hmm, I'm looking always to improve mileage. What's the reasoning behnid it?

Thanks!

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Volker_P
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Re: 81 CV carb vent TEEs

Postby Volker_P » Thu Jul 24, 2008 3:31 am

I would think what can come out of carbs at all is only fuel and/or air. So there can't be much wrong guiding this to the airbox. If the fuel fraction is relevant, then it might help for the mileage (and the environment).
But watch your plugs, the CV carbs may react on changed pressure conditions. Possibly the effect on mileage could be just that this turns the whole thing a bit further to the lean side.
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Buber
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Re: 81 CV carb vent TEEs

Postby Buber » Thu Jul 24, 2008 6:58 am

In that case, I will let it be. I'm waiting for UNI foam filter, that may lean the mixture some....

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Re: 81 CV carb vent TEEs

Postby Chris » Thu Jul 24, 2008 8:17 am

Volker_P wrote:I would think what can come out of carbs at all is only fuel and/or air. So there can't be much wrong guiding this to the airbox. If the fuel fraction is relevant, then it might help for the mileage...


That's what I was thinking.
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Re: 81 CV carb vent TEEs

Postby Volker_P » Fri Jul 25, 2008 1:32 am

I would try it, but carefully observe the plugs and the mileage. Free end hoses are always suspicious and susceptible to dust or rain. But possibly they are really required in just that way as a reference to the outside pressure, therefore the attention to the plugs.
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