Last one. High revs and ensuring the chain is sharp while cutting on a hot day can help. Higher revs are good as they mean more oil to the bar, less energy lost to the clutch, thinner wood shavings through less pressure on the bar, and more airflow. When a chain is dull the teeth do more thrashing than cutting and this heats up the saw. A dull chain means saw dust instead of saw chips or long slivers. Another indicator of a dull chain in summer is when the cut starts to smoke, which can also be a fire hazard. My making sure to have a file when cutting in summer is critical. I am also ready to sharpen every time the tank is filled, or more often if dirt is dulling the chain.
Long story short, in summer I remember to use fresh gas, prime with the bulb lavishly, carry and use a file, and while cutting remember that haste makes waste (keep high revs through little pressure on the bar, and allow a cool down before shutting it down).
