You will have to lean her out a little in colder weather.
Actually as Jesse stated the colder it gets, the more fuel you will need to add. There is more oxygen in the air so you will need more fuel to account for it. If you lean it out in winter from the summer tune, more than likely it will be so lean it won't run, but if it does run, it will run hot as hell.
And Adam, I'm really glad this thing is still chuggin' along. I know it had great compression but I was not sure how long that .15 would last. You have surprised me and it's lasted a lot longer than I figured it would. But I'm only talking about the piston and sleeve ($36 I think). Just wait until it snows! Water proof the electronics with some silicone or balloons or both, and have a blast in the snow. Those tires are great in the snow.