The stock tires on a Metro are the thinnest tires on any mass produced vehicle. I upgraded my size to a slightly wider tire for stability. Sure, it hurt fuel economy some, but why compromise safety? You already have one of the best MPG kings on the road and there are other ways to increase your mileage that will no effect safety.
An instant 5 MPG increase can be had by dropping in a 3Tech economy cam and gear.......
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