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Simple Cub under powered?

Hey! Love my Simple Cub but it feels really underpowered when I fly it. Today with mild winds (5mph or under) it was getting pushed around even at full throttle.

I'm running an EMAX 2213 935KV motor with 8x3.8 prop on a 3S 1300mAh battery in a power pod configuration. I'll have to measure AUW and post that for comparison.

Is anyone else running the same/similar power combo and happy with it? Would I get better performance from the FT branded 2218-1180KV radial on 4S?

Any suggestions would be appreciated!


Elite member
Good advice from @mrjdstewart - a 10x4.5 prop should see you right.

This is possibly another example of inconsistent or incomplete information being provided by FT on their product pages.

They recommend the Power Pack B for the Simple Cub (2213, 935kV motor). The power pack B comes with a 9x4.5 and a 10x4.5 prop.
Then under "needed to complete" for the Simple Cub they recommend a 370 sized, 1200kV minimum motor with an 8x4.5 prop
Then under the specs for EMAX 2213, 935kV motor product entry they state that it can handle 3S-4S lipo and 8 x 4.5 - 10 x 4.5 props (the product is shipped with two 10x4.5 props).

Its easy to see how someone who is piecing together components individually rather than buying the power packs could be confused as to what exactly to buy and think that an 8x4.5 prop would be suitable for use with this 935kV motor on 3S.

It wouldn't be too hard to update the descriptions to be more informative for first time buyers. Under "needed to complete" the could state that the motor should be 2213 to 2215 in size with 900-1000kV using 10x4.5 props or 1100-1200kV using 8x4.5 or 9x4.5 props.

Under the motor entry, for prop sizes they could add that the 8x4.5 is recommended for 4S and the 10x4.5 for 3S.

Or they could create a single table with the motors listed with optimal battery / prop / plane dimensions combinations and link to the table in all their power packs and plane kit entries (I know someone here is hosting such a table but FT should probably create one of their own and in doing so they may see how some of the recommendations are are not entirely consistent).
Wow - in hindsight I realized I did use the wrong prop. Looked only at the parts list and didn't pay attention to the prop motor combinations for 3S and 4S. My bad but glad someone is on top of this!
FOLLOW UP - I've repaired my Simple Cub with a new power pod (the old one was bent on the front due to the last couple of hard nose-on landings) and a larger (10x4.5) prop. I also had to rebuild the landing gear support as the wire had popped loose. I love how easy these foam planes are to repair!

It's all ready for another flight - maybe tomorrow morning if the weather is decent. Thanks again for the help!
Let us know how it went. I have the same set up as you do running a 3S 1400 and it does feel under powered. Weight without battery is 13 oz without landing gear and is really nose heavy with battery. wasnt the smooth fly I read about or expected. Trying to figure out what I did wrong??
Flew with the upgraded prop but still feels like it's wallowing. Maybe I'm not using enough throttle but I was wary of the full height corn field next to the RC field this weekend. DIdn't want to do a recovery so kept the plane close and probably too low/slow. Will try again next weekend at another field. I have the battery in the nose and it flies with the tail hanging down so high AOA.
Last time I flew mine (which has been a month), I ran it with a 1000KV motor, 9x6 prop, and 3S 1600Mah. Had to also add a few ounces of nose weight to help it balance. There were some light winds (not much more than 5mph), and it cut through just fine. Not exactly a speed demon, but nice cruising speed at half throttle. Here's video of that flight:

My motor ended up vibrating loose too towards the end of the video.
I should set my transmitter to alert me on my throttle settings so I know. But it seems on most planes, I stay around 1/2 to 2/3 throttle. Also, I seem to have this strange preference towards props with a 6 pitch...started when I fixed up that balsa trainer. So I have very little experience with smaller pitch props or slow fly props. A 6 pitch will give you a little more oomph than a 4.5 and draw more amps too so you do have to watch out for that. My ESC is 30A and it seems to handle it just fine.