would going up a size or two help or hurt fuel mileage. didn't know if the reduced rpm would out way the heavier tire.

This is one area where I'm sure Honda did their research. I would imagine that any change in tire size, accompanied by a recalibration of the speedometer, would have a negative effect, if at all measurable.

Not sure why you would want to fix something that isn't broke. Is there some specific reason you want to go up in size?

~H~
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