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mon-thurs 9-5 cst
This jet is for the Tillotson PK-1 clone carburetors. Not guaranteed to fit other clone carburetors. If you are using the Ruixing clone carburetors, they will use a different Lowside/EPA jet.
Low Side Tuning is a little more difficult than the main jet. The Low Side is going to affect the idle and low-speed acceleration. So we have two recommendations for tuning the low side jet.
For better acceleration, use .028-.034; this is almost exclusively for racing applications.
The idle will be rough, and, if left to idle, can foul plug fairly easily. As long as the engine is accelerating when going to wide-open throttle, you can keep adding low side jet. If it bogs then accelerates hard, then you could be rich go down a jet. If it's flat and slow to accelerate, it could be lean and go up a jet.
For better idle quality while still picking up some power, use .019-.022. We usually recommend those running mini bikes or recreational karts that need them to idle.
Note* The Tillotson PK-1A is richer from the factory, especially at low speed. You will use the lower end of the spectrum and sometimes lower than recommended for your engine to get the desired idle or performance.