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Mikuni carbs have excellent service documentation online free, sudco is a company name sometimes associated. The float height is specified in the motorcycles service manual because it is determined by the angle the carbs set on the bike as much as anything else. Usually very close to half way through the floats limit of travel it should stop flow of fuel.

Float level is critical because it makes a thing called the emulsion tube work well or not. The emulsion tube introduces bubbles into the fuel and starts the fuel atomization process.
 

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1982 kz440a
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He said it leaks while "running" that indicates that the petcock is only flowing while vacuum is applied therefore working properly. Dont go tearing the carbs apart again just yet, The problem may be much simpler. Remove the drain screws and inspect the tips. If they look like this:
Body jewelry Finger Wood Thumb Jewellery

Chuck them in a drill and spin them on a file until they seal properly. I suspect this is your problem because if the floats were too high you'd be complaining about your cylinders flooding and other poor running issues.
 

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1977 Suzuki GS750
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Discussion Starter · #23 ·
He said it leaks while "running" that indicates that the petcock is only flowing while vacuum is applied therefore working properly. Dont go tearing the carbs apart again just yet, The problem may be much simpler. Remove the drain screws and inspect the tips. If they look like this: View attachment 106756
Chuck them in a drill and spin them on a file until they seal properly. I suspect this is your problem because if the floats were too high you'd be complaining about your cylinders flooding and other poor running issues.
How will I know when I should stop filing them so they seal properly before putting them back on the carbs
 

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Somewhere there's a guy who had to determine the tolerances for that part. And there's someone else who had to test things to make sure they worked. And someone else who had to determine the capability of the process to manufacture the part to those tolerances. And someone else who had to check to make sure the finished part met the numbers on the drawing.

And then there's the guy who puts it in a drill and files it until it looks right.

Not criticising, do whatever works. I just find it funny (having been the guy who had to develop/check tolerances on things for a lot of years)
 

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1982 kz440a
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Somewhere there's a guy who had to determine the tolerances for that part. And there's someone else who had to test things to make sure they worked. And someone else who had to determine the capability of the process to manufacture the part to those tolerances. And someone else who had to check to make sure the finished part met the numbers on the drawing.

And then there's the guy who puts it in a drill and files it until it looks right.

Not criticising, do whatever works. I just find it funny (having been the guy who had to develop/check tolerances on things for a lot of years)
The tolerance on a drain screw is not critical. It's threaded, and it's soft. So as long as it's circumference is fairly uniform.... it will seal.
 

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So I finally have the time to do it now and where is the drain screw you’re talking about because the one on the bottom of the bowl looks nothing like that
Determine the model # of your carburetors and then google up a part list and/or exploded diagram of that make & model carburetor. That is how you find out what is in there without even taking it apart. :geek:
 
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