Topic: '81 CB650C CV Carbs- About ready to toss them in the lake!

[SpAmSoNiTe]

 Okay, I've got an overflowing #4 carb that I can't seem to stop leaking no matter what I try.  Comes out the little hole above/behind/to the right of the choke butterfly, or out from the main if I lift up the needle by hand.  I've got brand new float needles, read all of the tips about lapping the pressed-in float seat with valve compound and q-tip, and still havn't had any luck...  It's like the float just won't press that needle up there tight enough on it's own(I can hold it up and it shuts off the flow).  I tried swapping the floats, but that didn't make a difference either.  I am SOOO frustrated because the weather is a gettin' colder here in Ohio and she's been down for over two months now!  

Things I've tried out of desparation:

1. Swap floats
2. lap/polish float seat with a q-tip and valve grinding compound and toothpaste(by hand and in drill on low speed for <30 seconds)
3. Putting the float on backwards- not enough fuel in bowl
4. Riding the float needle on top of its groove instead of in it - not enough go-juice in bowl/float needle doesn't drop reliably

 Anyone got any suggestions before I toss these darn keihin's into Lake Erie???  Is there any adjustable floats that will fit the vb44a's instead of the fixed plastic ones?  

[Hush]

Did you swap the float valves when you swapped the floats?
It seems you said you swapped floats with no effect, the float valve is what seals up the bowl, try swapping the whole guts of the #4 carb and see if the problem follows.
Swap with #1 it's easiest.
If gas floods from the main needle if you lift it manually the float/valve system is definitely not doing it's job there.
Gas should be stopped below the bowl edge level, it should not rise enough to come from the main needle hole.
Also when you slide the float pin out, give it a bit of a light sand/polish with some emery paper, it may have a small burr or some crap on it.

[MRieck]

Are they OEM needles?

[MJL]

Is the float right side up?

[SpAmSoNiTe]

Hush- Tried swapping the guts between #3 and #4 carbs(carbs are on my mess of a workbench) with no luck..  I CAN lift it manually with the bowl off and it WILL shut off if I do it that way.  I've tried polishing the pin with some 1000 grit I had laying around with no sucess either.  when I have my tube on it to check the level, it tends to shoot clear up to the height of my tank, so somethin' definately ain't right ;P


Mrieck- They are non-oem needles.  K&L I believe.  I bought a four-pack of just float needles on e-bay and all but this #4 carb seem to be fine with them..  Although the old needles were fine with all carbs but #4 also.



MJL- I have tried the float in every which way that I could possibly put it on and have the needle still operate.. best luck actually seemed upside down, but the fuel level was WAY low..  didn't wanna try it on the bike like that in fear of excess lean or no fire at all.

Does anyone know what height the fuel is actually supposed to shut off at on these non-adjustable float/carbs?
Did you swap the float valves when you swapped the floats?
It seems you said you swapped floats with no effect, the float valve is what seals up the bowl, try swapping the whole guts of the #4 carb and see if the problem follows.
Swap with #1 it's easiest.
If gas floods from the main needle if you lift it manually the float/valve system is definitely not doing it's job there.
Gas should be stopped below the bowl edge level, it should not rise enough to come from the main needle hole.
Also when you slide the float pin out, give it a bit of a light sand/polish with some emery paper, it may have a small burr or some crap on it.

[Hush]

That's just insane man, you say if you fit a clear tube to the drain and hold it up, it shoots past the tank??!!
OK using Mr Spok reasoning, the only way that could ahppen is if the hole into which the float valve goes is completely blocked.
Follow me on this, if you lift the needle manually gas jets out into the carb so the needle is at least holding the gas back in the bowl, the clear tube trick tells you how full your bowl is, if it goes back up to tank level then your bowl is a sealed unit and nothing is getting out.
My solution.....remove #4 bowl and float/valve so you can get something very thin into there.
Something (old Q tip?) is blocking that valve hole, I'd use a needle or maybe a strand of wire that won't snap in there, maybe even fishing nylon.
Somehow you have got a blockage in there, apart from stripping the carbs off again that's your best shot.
Oh hang on did you say you had them on the bench?
OK now you know the problem...cure it.   I had some old rubber from my main gas line stuck in mine once and what a pain to get out of the feeding galley that runs across all the carbs.

[D]

Were you able to fix your carb(s)? I have been having the same problem