Another thing I thought of, be sure and open the bottom of the cowl, way open, for cooling. The engine can tend to overhead if you don't have enough air flow. This will cause a change in jetting which reduces engine power and cause more heat. A visious circle if you will. I learned this right off the bat, but I'm amazed that many people try to keep the cowls closed, I guess for looks, but it really effects engine performance. With the cowl cut for maximum air flow I've never had ANY heating problems, evening when hovering.
Good Luck,
Barry