For the top end, I contemplated whether or not to got one size bigger, but the cylinders looked just fine and I didn't want to spend the money on honing them. I ordered new stock size pistons from Japan.
Installing new pistons without honing the bores (at a minimum) is a complete waste of time and money. Your eyes are incapable of detecting out-of-round cylinders, wear beyond the limits of the piston tolerances, and more than likely the head and block surfaces are no longer flat. So whatever money you try to save now will very likely result in oil leaks, lower compression than stock, and burning oil. But it's your bike and time and money.
