Read the owners manual. find the idle adjustment screw and screw that a little. Wd40 all parts. The speed control cable may aso be causing it to never fully get back to the idle position.
Bad idle may refer to many things. Generally it means the idle is too high, too low, or there are misfires.
Idle adjustment set to high
Too high of an idle could be producing too much fuel for your jets to work with
the engine runs at a faster rate than when the idle speed is lower.
The idle speed is factory pre-set, and no adjustment is available. If the idle is too high, or too low, you will be having other problems that will affect the idle. In cooler temperatures, it will take the engine longer to come out of fast idle, as the engine warms up to operating temp. If the idle is too high/stays at a higher than normal idle, then take the thing to get it repaired. Running a car in gear(automatic transmission) with a higher than normal idle, can damage the transmission.
Idle speed is not adjustable. It is controlled by the engine copmuter. If your idle speed is too high or low you have a problem with a sensor or the idle air controll actuator. Also, a weak battery can cause the idle too be erratic
check intake plenum boot
You may have leak in the intake
P0507 : Idle control system, RPM too high.
Do you mean the rpm's on the tach? The bike should not run down the road at idle. At idle, in gear it should jump forward and die. If not, the idle is too high.
Either your fuel is burning too rich or you have an idle censor out. new idle censor's are not expensive
There are several things that can cause your 1997 Kia engine to idle too high. The most common cause is a malfunctioning fuel pressure regulator.