ORIGINAL: w8ye

There could be several other problems to consider . . .

Are you running NGK spark plugs? No, I will pick up a couple plugs tomorrow

Is the prop still tight as the wood crushes in the beginning? The prop is tight

The plug cap could be not all the way on the spark plug? Verified the cap is tight

The ignition timing sensor could not be picking up the magnet well - too far away - magnet weak - etc I will look at this, worked well for 2 tanks.