That's looks like my motorcycle exhaust, when my grandpa told me to use the fuel can off the back porch. I refueled and took off thru the pasture. Got back from checking the cattle almost dark when he holler, "come here boy". "What can did you use?" Evidently kerosene in a half empty motorcycle is just enough to run and run hot. Needless to say I didn't foul the plug for a while. He made me drain it and go get the right can. About whipped my end for using up his kerosene. Wish he could yell at me today, I would love to do something stupid for him to holler 'bout. Good ole days.