IMO you could lean the idle since you've run a gallon through. Don't think you'll hurt anything as long as the engine is a little rich. I check mine by squeezing the fuel line. If it speeds up before it slows down or stops, it's running rich. I leaned the idle on my 100 on the second tank of gas. Just kept sneaking the idle mixture in until it ran smooth, but made sure it was on the rich side of peak idle.