I would say to the OP to definitely not worry about heat issues on the ST. I just did a nice 300 mile loop out to the Oregon coast with a friend who has a new 1190 R. I asked him how the bike is working for him, and the one thing he mentioned was that the heat on his left leg was getting annoying. And we were in mid 60's temps. My old DL650 would heat up the seat in warmer weather, and when I rode a friend's FJR, the first thing I noticed was the heat dumping onto my legs. I find the S10 to be very good with heat management. I feel nothing on my legs while in motion, and obviously, nothing in the seat. The ONLY time I'm aware of radiator heat, is when the fan kicks on, and a gentle breeze from that direction makes the hot air drift back at me. But that's only when I'm stopped.