Float Height

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Wall
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Float Height

Post by Wall »

Below is what the manual says to do....I am still confused!! Is the person holding the carb upside down?


Image

When checking the float height turn the carburetor sideways with the float hanging from the pivot pin. Angle the carburetor back about 25° so the float is resting on the fuel valve but not compressing the spring inside of it. Measure the distance between the float bowl gasket surface and the highest part of the float with a set of vernier calipers or float height gauge.
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Gotanubike
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Float Height

Post by Gotanubike »

It's supposed to be standing straight upside down, on the hole where the carb slide and cap screws on. With the bowl off, you measure from contact surface for the bowl and the top(bottom) of the float

Image
1990 KDX200
Bike Profile -> http://www.kdxrider.net/forums/viewtopi ... 61#p136315
Suspension Overhaul(Shock+89-92 conventional forks) -> http://www.kdxrider.net/forums/viewtopi ... 15&t=15255
96'-98' RM125 Showa 49mm fork swap -> http://www.kdxrider.net/forums/viewtopi ... 04&t=16994
KDXrider world map! -> https://www.zeemaps.com/map?group=186158
Wall
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Float Height

Post by Wall »

is yours sidewways?
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Gotanubike
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Float Height

Post by Gotanubike »

Manual wrote:Float height is the distance from the float bowl mating surface of the carburetor body(with the gasket removed) to the top of the float. Measure the height with the carburetor upside down.
Not a PWK35 but same idea:

Image
1990 KDX200
Bike Profile -> http://www.kdxrider.net/forums/viewtopi ... 61#p136315
Suspension Overhaul(Shock+89-92 conventional forks) -> http://www.kdxrider.net/forums/viewtopi ... 15&t=15255
96'-98' RM125 Showa 49mm fork swap -> http://www.kdxrider.net/forums/viewtopi ... 04&t=16994
KDXrider world map! -> https://www.zeemaps.com/map?group=186158
canamfan
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Float Height

Post by canamfan »

I'll tell you how i set the float height on most carbs, it has always worked for me. Get a long enough piece of fuel line that you can put it on the carb and reach the other end with your mouth while holding the carb in front of you, so you can see the float. About 2 feet will do. Hold the carb out with the fuel line attached so you can see the float, blow into the fuel line and lift the float until air passes through or hold the float up and slowly let it down while blowing until air stops passing through. At the point the float seals the air from passing through, your float should be perpendicular to the carb body. If you look at the picture before this post, you can see the float is not quite perpendicular with the carb body. By blowing air through the float valve you can also see if it is sealing or not. This has always worked for me. I used to do all the measurements, then realized the floats always turned out to be perpendicular to the carb body anyway, after going through all that measuring. Good luck.
Wall
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Re: Float Height

Post by Wall »

Cheers guys. I have done it now! Its at 15mm.

Now for the fun to start tommorow trying to get it running properly again. I put the standard pipe back on it after taking off the full FMF Gnarly gold series. I wanted it a bit quiter. It has a 145 main and a 42 pliot jet in it. I had the problem of fuel peeing out the breather hose while it was on the side stand. My local dealer adjsuted the float height and when I put the carb back on it was idling really poor. When I tilted the bike it would die also if you put it in gear the revs drop really low like it wants to stall. Also if you gave it a big rev and let it come down again it would rev down and die....Plus when I tapped the float bowl with a screw driver it would die!


Any ideas? the only thing that was touched was a swap of the pipe back to stock and the float height! although i have now touched the air screw and idle. I set the air screw to 1.5turns..


Thanks for your help people you are a helpful bunch.. :supz:
Wall
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Float Height

Post by Wall »

Found my problem.

Basically when I tipped the bike from left to right or even pushed down on the forks it sounded like it was going to die.

I looked under the tank and saw that the fuel line was pushing against the throttle cable and causing it to crush.

I sorted this and its now purring like a cat...
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