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Jet, main jet, pilot jet, throttle needle, needle clip, fuel screw: How do they work?

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I rejetted my carb a few weeks ago .. and was wondering how all the different parts of the carb affect performance. I saw what looked like three jets on the underside of the carb .. jet, main jet, pilot jet .. how do these relate to one another? How does the throttle needle shape affect performance? Needle clip? What does the fuel screw do? How about those float bowls?

I heard that the pilot jet affects 0-1/4 throttle, throttle clip 1/4-1/2, throttle needle 1/2-3/4, and main jet 3/4-WFO .. is this right?

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Kinda. Your asking a pretty tall order man. So instead of writing an essay for you. I'll answer a few of your questions and others will hopefully answer the others as I am tired and drunk right now...haha. Anyone feel free to correct me if I'm wrong.

Pilot jet is longer due to the fact that when your at idle there is not as much gas sitting in your float bowl. Once you crack the throttle, float bowl fills, no longer need the pilots length and the main jet takes over, and hence, delivering more fuel into the main part of the carb.

The clip of the needle will determine how rich or lean you are running from about 1/4 to 3/4 throttle. The farther down the clip, the higher the needle sits, and as a result the more fuel is allows past it. A more agressive taper will also allow more fuel through.

Other feel free to correct or add.........

Check out the site "howstuffworks" there's lots of info and pictures about various different kinds of carbs.

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[quote=CANUCKSTER;6834834

Pilot jet is longer due to the fact that when your at idle there is not as much gas sitting in your float bowl. Once you crack the throttle, float bowl fills, no longer need the pilots length and the main jet takes over, and hence, delivering more fuel into the main part of the carb.

The float in the float bowl keeps the fuel at a constant level. Cracking the throttle does not control fuel level.

Use Google, there are a few sites that give the basics of carb function.

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