Re: slight problem with kit
The idle speed is adjustable several ways. First by using the idle speed set screw; the small screw with a spring on it found on the left side of the carburetor (if you have a 2 stroke, Chinese engine). Screw it in to increase idle speed and out to decrease.
The throttle cable is another way. Most, if not all twist grip throttles have an adjustment for cable tension where the cable attaches to it. Screw it in and it decreases the amount of pull. Screw it out and it increases the the cable tension. Also make sure you have no kinks or sharp bends in your throttle cable. It must work free.
A fast idle that can not be adjusted down can also be the result of an air leak somewhere in the induction system. Most common is the intake manifold to carb attachment and the intake manifold gasket. Both of these areas need to be sealed with a gasoline resistant sealer. Get back to us if these suggestions don't help. There are other approaches and other problems that we can look at.
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