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Discussion Starter · #1 ·
Adjusting float on CB 200. Book calls for 21mm.

Is this measured from the outside edge of the lip on the upper casting (which would lower the gas level) or the recessed or inset area where the gasket is ? (which would raise the gas level)

The PO had one carb set each way and obviously one way is wrong.
 

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lugnut said:
Adjusting float on CB 200. Book calls for 21mm.

Is this measured from the outside edge of the lip on the upper casting (which would lower the gas level) or the recessed or inset area where the gasket is ? (which would raise the gas level)

The PO had one carb set each way and obviously one way is wrong.
If it's like some of the other models, there is a little notch cut out of the flange that goes around the carb body. The bottom of that notch is the same level as the the base with the gasket installed. I'm pretty sure that's the location you should use.
 

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I was wondering about this, too. Here's one of my CB200 carbs with the notch (as Mike described) near the top of the photo.



Before my engine rebuild, I had the floats set at 21mm from the outer lip (so, less fuel) and the bike seemed to run a little lean. After the bike broke down I read more here and thought that setting was wrong so since the rebuild they've been set at 21mm from the inner area where the gasket sits (more fuel).

Now seems to be running rich. With both spark plugs, the electrode insulators are dark brown. The rest of the plug has black junk. I haven't yet isolated the issue to floats, but I'm still wondering whether I have them set correctly.
 

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Discussion Starter · #4 ·
Thanks to both of you for the updates to my post.
I do have the notch also.

The bike ran, but poorly, would not idle and break up when revved.

My bowl was overflowing, and I thought I had the adjustment wrong.
I tried it both ways and the bowl still pours out the overflow hose.
This in turn diluted my oil , so I changed that out.

I studied the carb further and noted micro holes in 1/2 the brass float and so I replaced it with another good used one.

I still have it overflowing !!!
This is a clean carb and I am running a temporary fuel container , so I can rule out rust particles.
The only thing left is needle and seat. I have the original OEM aluminum tipped needle. I'm sure the replacement is neoprene tipped.

I can't believe how much carb parts run for these little things. Of course everything is X2.
 

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Did you change the float needles and needle seats? It's pretty simple, if the fuel is coming out the overflow either the float needle is not shutting off the fuel or the float setting is wrong. The float height should be set when the float needle closses but DOES NOT compress the little spring.

Sometimes when setting the float levels people will turn the carb upside down and take the measurement. If the little spring is weak, the float will compress the spring and you will have an erroneous reading (in this case, the float setting will be to low). I usually set the float a little off vertical so the entire weight of the float is not resting on the spring.

This is a small point but MIGHT cause a problem.

You can kind of see how I did it in this picture.

 

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Discussion Starter · #7 ·
The second float I tried was worse than the first
(sunk like a battle scared submarine.)

I ordered a new pair from Babbitt.
 
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