I was experiencing way too much heat last summer and swore I'd never cut a trip short again because of it. I made a blanket out of the 1/4" insulation that is bubble wrap with foil on both sides which has I believe a class 1 fire rating. Bought it at local lumber store sold in various widths and purchased by the foot-cost me a whopping $6.00 to cover from the forks to beyond my burnt backside and down to my ankles. Home depot and Lowes sells a roll for $14.00but I was able to buy it in 4' width so have no seams. Be sure to use the foil tape at all cut's/seams and tuck it out as far as you can into the fairing behind where your knees go. This farkle has made my ST much more comfortable and enjoyable to ride in hot weather. To view picture search for title (Ridiculous amount of heat - left side).
Good luck
Rick
Good luck
Rick