Yup,... Idle "speed" screw,... raises and lowers the idle speed...
... but,...
Idle "mix" screw,... adjusts the amount of air to fuel mixture, at idle...
It is blocked off from the factory,... due to emission reg's in the US (tested at sea level)...
...but,... because America is such a huge country,... temps, elevations, and humidity's, vary wildly across this land... and this effects the needed ratio of air and fuel...
Then,...breathing mods, also need to be accounted for (air filters and mufflers)...
So,... we open up that plug,.. and adjust...
Evil as that may be, we do it,... 'cause we're rebels (Savages actually)...
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Buahhahhahhah!...
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