I tend to run on the warm side as well. I do always wear wicking base layers on the bike and they tend to do the trick for me. No need to go super expensive. I have a mix of Helly Hanson, Gore, Lidl, under armour and a few weird tk maxx specials. They all pretty much do the trick. Thinner ones for summer, thicker ones, or merino wool for winter. As I said on another thread, I tend to wear fully length layers (long legs, long arms) rather than shorts and t-shirt style ones. Although it may seem counter intuitive, it stops your skin "sticking" to your bike gear. Outlast is another "magical" liner available in jackets, gloves, trousers that can help to keep you cool, and warm. I have it in my gloves and it is fantastic. Definitely will be buying a jacket and trousers with it when I come to buying new kit.