I found a bandana with a handful of ice cubes rolled into a tube and tied around the neck does WONDERS for heat managment! It feels odd to have hot skin but not a hot head, if that makes sense...In fact, the first time I did this it was 104 for my ride home. I put too much ice in and started to get the 'brain freeze' headache about 6 miles into my ride home. Still had ice chips in the bandan when I got home, too! Fewer ice cubes the next day riding home and it was perfect!
"But its a dry heat!" my a**!!