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Discussion Starter · #1 ·
I'm trying to follow Clymer's instructions for setting this PD02A carb's float height, and not having fun with it.

They say to tilt the carb body "so that the float arm is just touching the float needle - not pushing it down." But that's tough, as there's very little clearance between the tang and the valve, thanks to the wire clip, so it's extremely difficult to tell whether the valve's movement is under its own weight (as the tang lowers the wire), or whether the tang is actually pushing on the needle.

Can anyone offer a clearer procedure for setting the float? Normally one inverts the carb and just measures the float height with the valve closed; presumably that setting would be a few thou lower than the .570" that Clymer calls for in their technique.

thx.mch.
 

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You can do it upside down but the float weight will likely depress the spring in needle tip to be slightly wrong. You must make sure the height is right while just BARELY touching that needle spring tip.

Be glad you don't have 4 of them to do exactly the same.
 

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Discussion Starter · #3 ·
Yeah, I get the difference - that's why I asked whether there's a good number (say, .560) for doing it inverted. I don't get why they don't just spec it that way to start with.

And yes, I'm grateful for not having to do duals or quads...
 

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Discussion Starter · #4 ·
Oh, I get it now... it's about the spring that I didn't know/notice is in the needle. Now that know what to look for, I'm pretty certain that the pin isn't at all depressed (i.e. spring not compressed) by the float weight when it's inverted.

Thanks for that.
 

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One other backup method to check is if the float shape lends itself toward it then make the float itself dead level to fuel bowl gasket face. That can work if the float is squared in shaping to give some straight line to set with. Most floats set correctly will be at or very near dead level at correct height, but you really can't see it with round ones.
 

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If your are wrong it will most likely flood or run lean, if lean you will most likely hear a little hammer in the Cylinder meaning you set the float so the fuel is low in the bowl. Usually replacing the needle and seat the float is still at factory setting and the gasket needs checked for thickness. I raised the needles one snap ring level to richen my 305, better cold starts that way. My friend had a 305 Yamaha that the Floats collapsed. It was auto inject oil and would hammer/knock like heck at 60 mph on a steady pull. I put in New floats & fixed it.
 

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Single carb is easy if you want to test it, just raise or lower the front of the motorcycle and see which way makes it stall out. Adjust it the other way (y) continue riding.
 
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