I really like testing new electronics. Improving the performance, feel and quality is something I continuously strive for. With the new LittleBee30A ESC’s a broader range of power setups are possible and I think I found the perfect combination for the Mini Tricopter. The Emax RS2205 2300kV drew too much current for the SN20A’s that we previously used. I was also concerned that the flight times would suffer with such a tiny motor. But it turned out that hovering flight time actually is the same (~14 minutes) as with the BE2208 on a 4S1800mAh battery. It’s not quite as efficient in the hovering throttle range, but the lower weight compensates for this, and it provides more thrust.
At full throttle this little motor draws 31A, producing 1200 grams of thrust, while swinging a 6×4.5 HQ prop. You would think this would fry the poor little copper strands in the motor, but with its built in cooling system which sucks air through the motor, cooling both the motor and the powerful N52 magnets, it can do this without overheating. This is quite amazing considering that the Emax RS2205 only weighs in at 30 grams with wires! It’s also incredible smooth thanks to the Japanese NMB Bearings, really high quality stuff right there.
With the Emax RS2205 the copter does feel more perky and crisp. The breaking force of the Emax motors are amazing, which gives a very accurate feedback.
If you plan on going over to the Emax setup, I highly recommend using some good quality batteries with high C-rating to feed these power hungry little beasts.
These motors are awesome! (Scary, but never the less awesome)
Was considering ordering a few more from Banggood for testing, but why wait 4-6 weeks for delivery, when I can have them delivered in a couple of days CHEAPER from RCExplorer?!? (Not even taking VAT and Danish Postal Services handling fee into account)
Great work David! ;-D
The lower weight might also help out for the servo speed, shame you probably can’t put tri-blades on em, but those are less efficient anyway. Downgrade to 1500mAh batteries and it might just get downright nippy.
Awesome, David! Have you seen these SunnySky 2207 2700kV motors (http://www.banggood.com/Sunnysky-X2207S-KV2700-Brushless-Motor-CWCCW-For-RC-Quadcopter-p-963449.html)? Would be interesting to see how they perform on the Mini Tricopter. But these Emax 2205s look great!
Ooo interesting find 🙂 Will test those out
Which thread do they have?
M5, I believe.
Oh, I meant left or right. These motors come in both CW and CCW variants, and as the recommended setup for a tricopter features counter-rotating motors, it would be handy to know which one do I order.
Doesn’t matter. It’s three-phase motors. Just switch two leads and it will change the rotation.
It’s about the thread on the shaft, not the rotation direction.
I would select all CCW threads to keep things simple and to just use a locknut that won’t get loose, even if the technically the prop isn’t “self-tightening”. Hope this helps!
Get them from David. That’ll guarantee that it’s right :D.
They are all CCW (normal threading) You can replace the included M5 lock nuts with integrated sleeve, with standard M5 lock nuts once you loose them 🙂
They are all CCW (normal threading) You can replace the included M5 lock nuts with integrated sleeve, with standard M5 lock nuts once you loose them 🙂
I’m tempted to try these too:
http://silver-drone.com/products/zmx-v2-motor-2300kv-2633kv-purple-cap
Hey David, given that these motors are designed to cool themselves, are they designed to spin in a specific direction? Wouldn’t the cooling effect be reduced of they were run in the opposite direction?
Also what about the air coming down from the prop and the air coming at the motor while you’re flying? That won’t disrupt the “cooling effect” of these motors? I’m just tired of manufacturers making bogus claims in the name of increased sales. Not saying these aren’t great motors, I just don’t believe they cool themselves any more than any other motor (in a real world application).
The cooling fins are symmetrical, so they work just as well in both directions. The cooling fins suck air in from the bottom of the motor and out the side of the bell. They move quite a lot of air. When running them on the bench without any prop on them you can feel a strong airflow to the sides. I can’t see the cooling effect being negatively effected by forward flight or prop wash, in fact efficiency of the circulation should increase due to the venturi effect. The airflow from flying fast forward should aslo increase this effect and the additional airflow passing over the sides of the bell should also increase cooling (as with all motors) Propellers generate very little airflow around close to the center, which during hover would mean that you get pretty lousy cooling on the motor just from that airflow. Pretty easy to test on the bench, which I did.
The DYS MR2205 motor which is the same stator size and very close to the same windings burned up on the stand within 15-20 seconds with 6×4.5 prop on it, in a tractor configuration. Where as the Emax RS2205 chugged through a whole battery without overheating. I knew the fins would do something, but I didn’t think they would be this efficient.
Can also add that the DYS MR2205 was drawing quite a lot less current as well. Closer to 25A where as the Emax was drawing 31A, which is 350W vs 434W.
Wow that is impressive! It’s good to know these motors really do stand up to the hype. I stand corrected! Definitely will be choosing these when I build my mini tri!
How much more performance do you get with new motors vs old. I have yet to assemble my mini tri I bought a month ago
They do feel quite a lot more nippy 🙂 Try flying it with the motors you already have first and get used to it. When you feel that you’ve mastered the performance of that setup you can start looking at other motors 🙂
You mention 14min hover flight time with that setup,whats your average “sport flying” and “slow flying” flight times, approximately, still 5min?