A simple way to match the motor to the prop?

Flying Monkey fab

Elite member
Well, pretty much the whole question in the title.

I inherited a couple of motors and I'd like to put them to good use but all the online calculators I've found have about 50 variables. Is there a simple calculator or rule of thumb to get me close?

They are 2826 2200kv BTW



Building Fool-Flying Noob
What I do is look the specs up on a supplier's sight or AliExpress/banggood.(Because they often put out performance charts with their motors. I look a several motors in the size and kv range (+-10%kv) of find arf models that use the motor,
Then I see what prop is recommended and start there. From that you can swap 1" diameter for pitch.
pay attention the cell voltage. (3S vs 4S) Can have a big impact.
ultimately the prop is converting Wattage (motor Power[Rated Amp draw x Battery voltage]) to a volume of air moved (or Prop lift) in a unit time. The chart below indicates a 7x3 or 4 prop.


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Site Moderator
Staff member
... Is there a simple calculator or rule of thumb to get me close?...
I agree with FoamyDM, look at a similar size motor & see what they recommend.
In the example above, they give a choice, 2S & 3S. In each case the larger prop is for 2S & the smaller for prop 3S.

I always recommend an on the ground prop test with any new setup. Run your prop at full throttle for 10 seconds or so. Then stop & take the temperature of the motor, ESC & battery by touching them. Warm is OK but if anything is so hot you don't want to hold it STOP, the prop is too big. If it passes, try a 30 second run & take the temperatures. If it passes, try a 60 second run & take the temperatures. If it passes, go for a fly or repeat with a larger prop. A watt meter is helpful but not necessary.

It always a good practice to take the temperatures when you land. Keep in mind that a prop that worked when it is mild out, 70's, may be too much when it gets hot outside, 95+.
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