carb leaking.

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carb leaking.

katman
Hi everyone,
Just had the carbs on my 77 rebuilt. Put them on. While I was having that done I adjusted my valves.
After riding the bike I have a mis or stumble off one cyl. at low speed . I noticed when I came back and parked I had fuel leaking from the #2 bowl overflow tube. Would this cause my miss, and would the
float be sticking or have I adjusted my valves wrong. As allways thanks for the help.
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Re: carb leaking.

Re-run
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Almost always a float valve stuck. Try tapping it with a screw driver handle. If it still leaks, then drop the bolw, remove the float, and clean the float pin seat. A Q-tip and carb cleaner usually works well.
The ride IS the adventure. The destination is just to get gas!
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Re: carb leaking.

shinyribs
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If your slow speed miss is associated with your float bowl overflowing you should see a puff of black raw fuel smoke as it happens.I dont know how you would safely check for that while riding,but it would be a way to tie the two symptoms together. But a low speed miss and an overflowing float bowl do go hand in hand.It would be a good place to start
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Re: carb leaking.

katman
In reply to this post by Re-run
Hi everyone,
I took the carbs back off and removed #2 float baow and cleaned the needle and seat. All new parts
are inside and looks to be a good job. I am waiting on some points and haven't ridden it again.
I am still getting some gas dribble out of a couble of the overlow tubes while sitting. I don't know what
I should be looking for besides sending them back. Is this normal for alittle leakage.
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Re: carb leaking.

shinyribs
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No.There should not be any leakage at all.When i rebuilt my carbs i put in new rubber tipped needles and they leaked like a sieve.I put my all metal needles back in and have no problems since.
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Re: carb leaking.

Lucky 1
This post was updated on .
In reply to this post by katman
Before adjusting your valves did you adjust your cam chain to take the slack out of it?

If you think you may have adjusted your valves wrong you need to go back and just check them.
After you check each one and you are sure it is within in limits then you will know you have done it correctly.

To check them do this:

If the clearance is supposed to be .004 thousandths,... take a .005 thickness gauge and try to insert it.
If it will not go then you must have the .004 as specified. Check it with the .004 as a final check just to make sure it is not .003.

Same for the intake. If it is supposed to be .003 then take a .004 thicKness gauge and try to inset it. If it will not go then you have .003 and it is correct. Check it with the .002 as a final check just to make sure it is not .002.

See what I mean?

About the leaking float bowl drain.
On the 1977 carbs if it has the accelerator pump you will need to do 4 things.
1. Remove the carbs. No way out.
2. Remove the float bowl after you have drained the gas out. And make sure the small O ring is in the
top edge of the float bowl where the accelerator pump check valve is.
3. Turn the carbs upside down and check the float level.
4. Fire the guy that rebuilt the carbs. Do not let him work on your bike anymore.
Also if he did not put in NEW float needles then you will have to put in new float needles.
You cannot rebuild motorcycle carbs and not put in new float needles.

If the floats are this style then this is what it will look like when the floats are .570 above the surface of the carb body when the carbs are upside down.
Do not push down on the floats to make this line up. Make adjustments to the float tang to line it up.

On a Roadstar Adventure.
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Re: carb leaking.

TOOLS1
Administrator
This post was updated on .
Is he is talking about the needle valves in the carbs. 
Have, you tried adjusting the floats? They will need to be bent down.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: carb leaking.

Re-run
Administrator
In reply to this post by Lucky 1
One things about the valves, on the 750 sohc, the valve train likes to be set to .003 and .004. This allows for better heat expansion and saves wear on the train. I know what the manual says but practical experience of mine and other people points to just a bit more gap being quite beneficial.
The ride IS the adventure. The destination is just to get gas!
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Re: carb leaking.

katman
Man this forum is great. I will check the float level when I take them back off tonight. Should I check
them upside down. I have seen some articles were they check them with the carbs on there side.
The guy is sending me a fresh new set of seats and needles  to replace. going to go back and adjust my valves to .003-.004. will let you know. Keith
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Re: carb leaking.

TOOLS1
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Upside down is how I do it.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)