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Offline kopptl

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setting floats?
« on: September 25, 2009, 10:19:18 am »
i know my floats are supposed to be set at 26mm. how do you set them?? i have read that you should tilt the carbs so that the float just sits on the needle and does not push the needle down?? this true?? i just turned them upside down and set them on my bench. this right?? could this contribute to not getting any gas??
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Offline Johnie

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Re: setting floats?
« Reply #1 on: September 25, 2009, 10:29:31 am »
Don't just tip them upside down. You want to tip them slightly on their side to where the float tip just touches the tip of the needle valve. Set your 26mm from there.
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Offline flybox1

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Re: setting floats?
« Reply #2 on: September 25, 2009, 10:42:44 am »
Quote from: Johnie on September 25, 2009, 10:29:31 am
Don't just tip them upside down. You want to tip them slightly on their side to where the float tip just touches the tip of the needle valve. Set your 26mm from there.
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Offline Gorms

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Re: setting floats?
« Reply #3 on: September 25, 2009, 11:10:16 am »
At least of my '77, the ends of the needle valves are spring loaded.  Adjust the float height from the point where the tab on the float is just about to compress the spring, not to the point where it just touches the end of the valve.
« Last Edit: September 25, 2009, 11:12:58 am by gorms »
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Offline BVCB650

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Re: setting floats?
« Reply #4 on: September 25, 2009, 11:24:38 am »
Mine is at 1/2 inch from the gasket surface when the needle just makes contact with it's seat.
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Offline Johnny5

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Re: setting floats?
« Reply #5 on: September 25, 2009, 11:59:10 am »
Just curious why it matters if the carb is upside down or not? If the needle valve is seated, and you adjust the float so it just touches the needle spring pin, then if the carb is on its side, or upside down, wont you still be getting the same reading? Is the needle valve suppose to not be seated when making this adjustment? If so, then I've been doing it wrong.

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Offline BVCB650

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Re: setting floats?
« Reply #6 on: September 25, 2009, 12:04:26 pm »
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Offline kopptl

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Re: setting floats?
« Reply #7 on: September 25, 2009, 12:54:26 pm »
thanks for all the advice!!
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Offline Johnie

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Re: setting floats?
« Reply #8 on: September 25, 2009, 01:51:47 pm »
Quote from: Johnny5 on September 25, 2009, 11:59:10 am
Just curious why it matters if the carb is upside down or not? If the needle valve is seated, and you adjust the float so it just touches the needle spring pin, then if the carb is on its side, or upside down, wont you still be getting the same reading? Is the needle valve suppose to not be seated when making this adjustment? If so, then I've been doing it wrong.


Probably because that is the way Honda says to do it in the service manual. At least my KO manual says to do it that way. They must feel the float is to heavy and would depress the needle spring a mm or two allowing the float level to not be set spot on.
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1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
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Offline kopptl

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Re: setting floats?
« Reply #9 on: September 25, 2009, 01:54:45 pm »
could just turning them upside down and  setting them that way(which i did, wasnt thinking) be part of not tgetting gas?
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Offline Johnny5

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Re: setting floats?
« Reply #10 on: September 25, 2009, 03:20:49 pm »
Oh okay, I got it right then. As I will sometimes hold the float in place to not depress the needle spring when checking the heights.
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Offline w1sa

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Re: setting floats?
« Reply #11 on: September 26, 2009, 04:17:40 am »
Quote from: kopptl on September 25, 2009, 01:54:45 pm
could just turning them upside down and  setting them that way(which i did, wasnt thinking) be part of not tgetting gas?

Yes.
If the method you chose is not applicable to your model's carb float setting procedure, it will (most likely) result in the float/valve  contact point occuring at an earlier point/lower fuel height in the bowl during operation.
 
If that point is outside the acceptable operating/design parameters, the fuel level will be maintained at a lower level and will not be drawn thru the jets as efficiently.

Normally, more than a mm either way in the setting may deem the setting to be unacceptable for efficient operation/tuning.
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