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Guys what am I doing wrong? v. Float level

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Ok, so I had my carb apart and I went ahead and gave it a cleaning. I wanted to check the float level so i followed the instructions in the thread "Is your two-stroke running rich". I'm having the following issues. This is what his float looks like when it is completely upside down. You can see that the top of the float is several mm's above the gasket surface.


This is what mine looks like (sorry for the bad pic)


As you can see, my float hardly sticks above the gasket surface at all. Is this normal for a 2002 YZ 250? I then proceeded to tilt it at a 45 degree angle so that I could take the measurement without compressing the spring loaded bumper. The tang is resting on the spring loaded bumper but is not compressing it at all in this pic. This is what it looks like.


From what I understand, that line you see on the float(where the two halves of the float were put together) is suppose to match up with the gasket surface. The way the float sits, it's impossible to line up both sides of the float to be parallel to the gasket surface. On the right side of the float next to the pivot pin, in the second pic, to make that side come up any higher the pivot pin would have to be seated higher. Now lets say that this is normal. Do I just measure the highest point of the float from the gasket surface to set my float level? My repair manual says the fuel level (which Im guessing they mean float level) is 9.5mm-10.5 mm.


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Just did some searching and found an easier way to do this. I guess I need to drill a small hole on the float bowl drain plug, insert some clear tubing in it and then attach the carb back to the gas tank. Switch the fuel on and let the carb fill up with fuel while holding the clear tubing above the float bowl. My goal is too adjust the float until the fuel in the clear tubing goes up the where the gasket in the bowl is. Problem is I don't have a spare drain plug and I dont think anyone sells one locally. I guess I can order one but I want to ride today!!! I haven't been able to ride for almost a month because of bike issues :smirk:

Edit: Found another post on the subject

No. Yamaha doesn't give any specs on what the float level should be. All they say is how high the fuel level should be. Without knowing the buoyancy of the float in fuel, you can't get an accurate measurement of where the bottom of the float should be in relation to the body of the carb.

Seems like the only way to change the float level is using the clear plastic tubing. Does anyone know where I can buy a drain plug forthe YZ 250 that already has a nipple installed so i can just put the tubing on that instead of drilling a hole? Thanks

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