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Hello. My name is Tan.
What was your initial setting for the idle jet?
The only way to find a misfire is with the use of a timing light. Connect the timing light to the top cylinder run the engine till it misfires while watching the fl;ash of the timing light. The light should have a steady flash with no dead spots. If you see any dead spots move the ignition coil of the misfire to the other cylinder. Now test again did misfire move to the other cylinder or stay?
Ok that is correct. That is just the initial setting then when in the water and warmed up fine tune the adjustment to get the best idle. Which sounds like you have already done. That leaves the timing light test for a misfire.
Do you have a timing light to do this test?
Is the spark inconsistent on both cylinders?