What I've found interesting is riding out west. Last May I crossed the western deserts/mountains and typically had temps in the 30 to 40's at my sunrise departures. By mid afternoon I'd be in the triple digits. I control my comfort with layering. As the temp rises a layer comes off, I end up with a tee shirst and a mesh jacket. Riding pants stay the same but insulated underwear might be put on and removed as the day goes by. But that's inconvenient and I don't mind the cold or hot on my legs as long as my torso is comfortable. I've read and i've found it to be true that normal skin temp is about 93 degrees. Once the air temp exceeds that then it's time to start blocking airflow by extending the windshield. Re hydration can't be over emphasized. For just local riding I don't like hot temps and avoid them , but if I'm on a cross country trip the enjoyment of travelling to new places overcomes my discomfort.
Bill
Bill