Smaller Pulley = less heat + same range?

[hummieee]

Could compare the wattage needed to go some same high speed with both upside down on the table and see how much the drivetrain is sucking

Larger motor pulley = more efficient?

Maybe the pwm rate could/should be altered as well for best efficiency of motor and esc [Look at how ESC PWM Rate impacts Efficiency! Brushless Motor Dyno] This guy shows the higher the pwm the more the whole system is efficient. But what of duty cycle? It influences both esc and motor efficiency.