curb and off idle
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Joined: Jan 2001
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From: Virginia
Curb idle is when the gas pedal is not pushed at all, and the engine is idling on it's own. Off idle is when the gas pedal is being pushed, and the rpms increase, but not enough to turn the main fuel circuit on in the carb.
You cannot readily set the off-idle mixture. The off-idle mixture is set with orifices pressed into the carb. You can usually set the curb idle with a throttle stop screw near where the gas pedal linkage is connected, and you usually can set the curb idle mixture with the mixture screws somewhere on the carb, depending on the model. Note, most newer carbs that have never been rebuilt will have caps on the idle mixture screws, blocking you from adjusting them.
You cannot readily set the off-idle mixture. The off-idle mixture is set with orifices pressed into the carb. You can usually set the curb idle with a throttle stop screw near where the gas pedal linkage is connected, and you usually can set the curb idle mixture with the mixture screws somewhere on the carb, depending on the model. Note, most newer carbs that have never been rebuilt will have caps on the idle mixture screws, blocking you from adjusting them.
