if you have been riding in the heavy rain over the last few days, it is possible that:
1 - water/moisture got into the front spark plug and shorting it.
2 - pour some water over your tank, then open the fuel cap and check the edge to see if there is a small pool of water, if so you may water in the fuel, caused by a blocked drain pipe.
both common causes for misfireing, it happened to me
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