Reido,
Here in New England its seems to get cold for several months of the year. We even get this white powder that falls from the sky
A sweatshirt may work ok in the south west, but up here in the north country give me a Lectrik Vest, an leather jacket. Dont get me wrong I will ride with just a Tee shirt and jeans when the temps get into the 80s, but this time of year I start adding layers.
Mark
