Squishy inspired me to brush up on my motor technology so I will share the fruits of my research with you. With a sufficient battery and ESC, you need to know four other things to pick the correct prop size; 1) Motor KV (RPMs per volt) 2) The power behind it (watts, amp draw, or torque) The weight of the motor is a good indicator of this. 3) The dynamics of the plane (the wing loading and aerodynamics) 4) The way you like to fly the plane The dynamics of the aircraft deals with friction and momentum; it is information like the weight, Air flow obstructions and the aerodynamics of the air frame. Any time you change your plane’s set-up or run it in weather you're not use to flying in, land it and check the temperatures every 30seconds to a minute. Touch the ESC, battery, and motor with your bare finger and if you can't keep it there for more than a couple seconds, it's way too hot. If anything is getting too hot, sometimes you can fix it with throttle management. Do the lands and checks until you get a good sense of how hard you can push your Jet and not damage the electronics. If you have to manage the throttle more than you want to, or the problem is beyond throttle management; it’s time to upgrade a part or two. If you are trying to fix a heat problem, one of the best parts to change is the prop. Too much prop can overheat everything. More length, more pitch, both draw more power (current, amps), so you must find the right balance of the two to choose the right prop. If the motor temperature is OK, the prop length and pitch are OK. Too little prop waste energy. Two of the most important things that determine the KV rating of a motor is the number of turns and the thickness of the wire used in the motor windings. KV refers to the number of RPMs per volt at no load or with no prop. With a 11.1Volt battery, a 2200KV motor without a prop, will run at 24,420 RPM (11.1 x 2200=24,420). But the KV rating will tell you a lot more then what propeller you need, it tells you the temperament of the motor. The KV represents intent, and the motors amp draw represents the strength toward reaching that intent. A Park-Jet motor is 1800kv to 2600kv, 20amp to 65amp, 2cell to 3 cell, and a 5 to 7 inch prop with a 3 to 5 pitch. The main reason Park-Jets use high KV motors is there are a lot of advantages to the mid motor configuration, but we have to keep the prop slot as small as functionally possible. With rear mounted thrust vectoring, a high KV motor is also preferred because a low KV motor with a big prop eats the back of your plane when you turn. The big advantage of a lower KV motor is “it gives your plane great thrust while only using a light two cell battery”. You can substitute a high KV motor with a light three cell battery with less milliamp hours (mah). The difference you will see is shorter run times, and a little less torque due to a longer wind up time. The lower Kv motor is normally wound with more turns and a smaller diameter wire; because of this, it can handle less current. For this reason, a 2 cell Lipo is preferred to power it. More torque while using a smaller, lighter battery is a great combo for a 3D plane. The higher the KV: 1) The less prop it will drive (less length) 2) The longer the motor takes to wind up. 3) The less torque per volt, 4) The less voltage you need to get power 5) The more speed (the higher the motor will wind) 6) The bigger the wire with less turns in the windings 7) The more current it will take 8) The more voltage it will take 9) The higher the maximum power output.(see note) 10) The more efficient the motor is NOTE: More power is not necessarily more thrust, prop size and efficiency comes into play there. A lot of these are generally true, but not true in every case.