Make sure the spark plug cap is on correctly.
I know I had a minor issue with this one time after id washed my old xtr as id knocked it off but not completely.
also a good old spray of wd40 in there to make sure any water in there is dislodged
appart from that if theres no loss of power might be dirty fuel, air starvation/dirty/blocked air in take
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 Plough on
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