Seventy is hard to figure out for me. I'll do shorts above 65, but the top layer is hard. If it's 70 at the start, I'll wear arm warmers and sometimes a vest over short sleeves, so i can peel the layers. If that's the highest it will be, I might be in a thin long sleeved jersey. Denise always has less clothes/layers than me when we ride, but I am slowly getting used to feeling cool at the beginning of a ride. Don't like it, though.