CBR 1000F "Hurricane" 1987-1996 CBR 1000F

How do I adjust floats?

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Old 09-10-2006, 09:15 PM
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Default How do I adjust floats?

I think I goofed up - I tried to adjust the floats a little higher, only way I could see doing it was to bend the little round things attached to the ends of the float valves - now bike won't start. Help anyone?
 
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Old 09-10-2006, 11:53 PM
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Default RE: How do I adjust floats?

The little tang that sticks toward the float and touches the top of the float needle is what is bent. And you only have to move it a thousandth of an inch up or down to change the level. Here's a site that describes it: http://www.salocal.com/sohc/tech/car...mgs/flthgt.htm
 
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Old 09-11-2006, 09:07 AM
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Default RE: How do I adjust floats?

I have a '94, which has a different float setup than other years, and doesnt look like your picture. The float valve is #23 in pic - it is a float valve that has attached a small post with a small round thing that works with the plastic floats - there is no "tang" or anything that looks like something you can adjust. Please help me figure this out I'm stumped.
http://www.ronayers.com/fiche/200_03...00&parent=5440
 
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Old 09-11-2006, 02:54 PM
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Default RE: How do I adjust floats?

chesthing, I have not seen a float that could not be adjusted. I haven't had one of these carbs apart yet. Is part #23 all plastic or is there a brass piece where the pin holds the float in the bowl? It looks to me that where the needle is attached (slips in) is where you would adjust this type. I have adjusted ones that look like this type. There is no tang so you use a small screwdriver to spread the tang thing that holds the needle, this will let less gas in. Or use needle nose pliers to pinch it tighter to let more gas in raising the bowl level.
 
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Old 09-11-2006, 03:24 PM
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Default RE: How do I adjust floats?

#23 looks like a float valve, a small brass pin holds a small brass circle that rides in between the plastic float assembly. I originally bent the edges of the circles up a little to try to raise the level, I think maybe the float valve wasnt coming out enough to let enough gas in? I took them out again and best I could straightened them with some plyers - floats went up and down smoothly with gravity, so I reinstalled on bike. I crank and crank, and nothing - I then opened the drain screw on the carbs I can reach and no gas comes out - wth is going on? you think I should take them out again and bend the edges of the circles down? I seriously see no way of adjusting these because the floats close the valves with a plastic line that contacts the circle straight across the middle of them..
 
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Old 09-11-2006, 04:22 PM
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Default RE: How do I adjust floats?

Yes, the semi-circle thing is where, I think, you should do the adjusting.
The more you squeeze it togeather the higher the level would be. You have to think in reverse.
You do the adjusting with the carb upside down to get the float needle to seat using gravity and make your measuremant to the gasket serface. When the carb is back on the bike the gas lifts the float (as did the gravity upside down) seating the needle and shuting off gas flow.

Not to be a wiseass but, did you rember to turn the pitcock to on? Even with the float level not set correctly you should have gas in the bowls. It may be too low but you should have some.
 
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Old 09-11-2006, 06:36 PM
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Default RE: How do I adjust floats?

Well, I just started it up and it seems to run about like it did with a flat spot between 1-3k. Last night I couldn't get it to start for like over an hour of trying, I have no idea why sitting overnight "fixed" the problem.
 
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Old 09-12-2006, 02:03 AM
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Default RE: How do I adjust floats?

"#23", also known as the float needle, is not what you should bend. There is a thin metal tang that bridges the gap between the two plastic floats that the float needle "hangs" on. This tang is what moves the float needle in and out of the needle seat, which in turn shuts off or allows fuel flow. This metal tang is what you bend up or down depending on if you're raising or lowering the float height. If you are raising the float height, you bend the tang down toward the bottom of the float bowl. If you are lowering the float height, you bend the tang up towards the carburetor bodies. The problem you're having, however, sounds like a jet needle problem. Do you have a jet kit installed in your bike? It sounds like you need to raise the needle one position which is accomplished by lowering the circlip in the jet needle one position downward. The "flat spot" you are feeling is a lean condition which occurs when you open the throttle and vaccuum causes the needle jet to be raised. The needle, however is too low and remains in the main jet port too long so there is too much air and not enough fuel entering the combustion chamber. By raising the jet needle one position, you will enable the needle to open up the main jet port sooner and allow more gas to enter the combustion chamber.
 
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Old 09-12-2006, 02:58 AM
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Default RE: How do I adjust floats?


ORIGINAL: chesthing

Well, I just started it up and it seems to run about like it did with a flat spot between 1-3k. Last night I couldn't get it to start for like over an hour of trying, I have no idea why sitting overnight "fixed" the problem.

You didn't happen to have it flooded did ya? Just curious. While trying to start it, the jets could have been plugged, or by chance the amount of draw the engine put on the carbs, wasn't enough to fill the bowls? Not sure. Just my 2 cents.
 
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Old 09-12-2006, 11:42 AM
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Default RE: How do I adjust floats?

No fuel was getting in the carbs - not flooded. As far as needles, I installed the Dynojet needles with the circlip on the top position, bike ran better but my mileage went from 42 to about 32 and the guys I ride with all smelled fuel following me. I went back to the stock needles - the are much longer than the Dyno's at the top position and much fatter. I'll just live with the low rpm flat spot - others have said the same thing when they installed the V&H exhaust, I didnt have it before the exhaust change. It's an acceptable tradeoff for weight savings and sound.
 


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