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Carb balance/adjustment frustration [long]

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William, the only way to adjust float level on the all plastic float is by putting washer/s between the float lid and the needle and seat assembly. As mentioned about with the float attached to the float lid with the needle and seat installed you should be looking for about 1/8"-3/16" between the float lid and the lowest portion of the float while holding the float lid upside down.
 
When you think you have the level set correctly, do as noted above and fill the float chambers. Then run the main jet down until you just exactly reach the level of the fuel in it's center. Use a magnifying glass if you are an "old guy". Do this slowly so you don't "over drop" the jet. When the top of the jet is dead on with the fluid level, measure the jet depth from the top of the bridge with the butt end of a vernier caliper. It should be around 1/8" or so as also noted above. The trick is and what you are looking for though is to have BOTH carbs set at the exact same jet depth. This of course results in the exact same relative exposure of needle-to-fuel level for both carbs. If the measurements are off go back into the float chambers and shim the needle seat as Hap suggests to gain the proper fuel level. You might have to repeat this process several times in order to get both levels to match dead on. Then you run the jets back up to exact bridge height and then back down between 70 and 80 thou, (80 thou for an overall slightly richer mixture for any given amount of piston rise), be sure to match them exactly, to have a beginning point for your mixture adjustment phase of the tune.

BTW: Don't use the lift pins to raise the pistons. If you do there is no way to be sure that you are lifting each exactly the same. I use an SU gland nut wrench laid on it's side to hold the piston up. That way I know that the pistons are raised exactly the same amount. Jack
 
For itty-bitty better response you can adjust the level in the jet higher.

I like 1/16" down from the top.

(if you like to play) /ubbthreads/images/graemlins/grin.gif
 
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