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Here is my two cents.
I have pods and 4-1 also on my 79 special and my jetting is 145 mains and 45 pilots. Jetting recommendations say to up the pilot one step for each three steps up in main jet as a rule of thumb. I jetted from the top down using the FactoryPro CV Carb Tuning procedure and it seems to confirm the carb tuning recommendations.
The pilot system runs idle and cruising up to about 1/4 throttle and then contributes some all the way to around 1/2 throttle opening. After that its mostly all the main jets. So the pilot system is important as that is where you do much of your riding. Even cruising at interstate speeds you are still partially on the pilot system.
A simple way to tell if you need more pilot jet is the idle mixture screw adjustment. That screw is only controlling one of the 3-4 pilot system outlets into the airstream. Staring point is 1-1/4 turns out from LIGHTLY seated. If your idle is not smooth unless you are turned out 3 or 4 turns or more then you are probably light on the pilot jet making the whole pilot system on the lean side. As soon as the main start to come in then wham-o, you are off like a rocket. (Wham-o is a technical term
) Up that jet one number and you will find your idle mixture screws will be back around 1-1/4 or 1-1/2 turns out and that means your otherwise lean situation will go away. But first you must have the correct main jet installed.
I have pods and 4-1 also on my 79 special and my jetting is 145 mains and 45 pilots. Jetting recommendations say to up the pilot one step for each three steps up in main jet as a rule of thumb. I jetted from the top down using the FactoryPro CV Carb Tuning procedure and it seems to confirm the carb tuning recommendations.
The pilot system runs idle and cruising up to about 1/4 throttle and then contributes some all the way to around 1/2 throttle opening. After that its mostly all the main jets. So the pilot system is important as that is where you do much of your riding. Even cruising at interstate speeds you are still partially on the pilot system.
A simple way to tell if you need more pilot jet is the idle mixture screw adjustment. That screw is only controlling one of the 3-4 pilot system outlets into the airstream. Staring point is 1-1/4 turns out from LIGHTLY seated. If your idle is not smooth unless you are turned out 3 or 4 turns or more then you are probably light on the pilot jet making the whole pilot system on the lean side. As soon as the main start to come in then wham-o, you are off like a rocket. (Wham-o is a technical term
) Up that jet one number and you will find your idle mixture screws will be back around 1-1/4 or 1-1/2 turns out and that means your otherwise lean situation will go away. But first you must have the correct main jet installed.
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