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Brushless confusion, help me choose!

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Just getting back into the scene after years away. In the past I ran nitro, now I'm going electric. Finally figuring out this lipo and brushless stuff, but I'm at decision point. 

Awaiting my new TT02 White edition kit in the mail, and I need to order a motor/esc combo but I have no idea where to even begin with regards to what I need. 

Here's what I know: 

1) It has to be compatible with the 2s lipos I already have. (One 4000mah and one 6500mah)

2)I need both motor and esc so a combo makes sense. 

3) Want to keep price around $100 or less.

This article has a ton of options but I don't know what the differences are. 

https://www.onkidstoys.com/top-21-best-esc-motor-combos/

I'm going to be racing at a local track doing rally. The guys who go there suggested this combo: 

https://www.hobbytown.com/xerun-justock-zero-spec-sensored-brushless-esc-motor-combo-13.5t-by-hobbywing-hwa38020401/p453305

This is one I keep seeing advertised:

Http://www.horizonhobby.com/KXSS0500?utm_medium=display&utm_source=criteo&utm_campaign=productremarketing&utm_content=KXSS0500&CA_6C15C=320011980000459400

Happy to take suggestions. Don't need the world's fastest motor but I'd like to be competitive.

Thanks!

 

 

 

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Brushless (BL) motor basics - one on one... 

With Brushless motors, the ESC sends pulses to the windings in the brushless motor stator, and this creates a rotating magnetic field in the motor that then interacts with the rotor, and causes it to turn.. There are 2 types of brushless motors, sensored and non-sensored (or sensorless).. Sensored motors will have 4 wires/leads that run between the motor and ESC and non-sensored BL motor will only have 3 wires that run between the motor and ESC.. (The extra lead on a sensored combo is the sensor lead..)

With non-sensored BL motors, there is no real way for the ESC to know if the rotor is turning at the same speed as the rotating magnetic field at lower RPM's, and you can get what is known as "cogging" which basically the rotor skipping or slipping in the rotating magnetic field.. At higher RPM's, the ESC does get some feedback from the motor, and it allows the ESC to adjust the rotating magnetic field to suit..

Sensored motors however have a sensor board inside the motor that allows the ESC to know the position or RPM that the rotor is spinning at, even at low RPM, so you don't get the "cogging" issue that you see with non-sensored BL motors.. Sensored BL ESC's can also adjust the timing and boost of the motor electronically, which can give some nice gains in performance..

With that said, if you are planning to race, then many clubs stipulate that you need to run a sensored motor and ESC combo.. You also may want to check with your local track if they have a motor limit in the class save you buying a motor that is too fast or slow for the class you're going to race in....

There is no exact speed or performance comparison for brushed to brushless motors.. Brushless motors typically have a lower RPM than brushed motors, but Brushless motors typically have more torque, so you can gear them taller (fit a larger pinion gear) to get more speed from them..  A 21.5BL motor will be about as fast as a kit supplied 27turn silver can brushed motor.. A 17.5BL motor will be about as fast as a Tamiya Sports tuned or old 27 turn stock brushed motor.. A 13.5BL motor will be about as fast as a 19-23 turn brushed motor (eg the 23 turn Tamiya BZ,TZ, RZ motors)..

The 13.5 Hobbywing XERun Justock sensored combo that the guys at your club recommended should work just fine..  The HobbyKing Trackstar Combo that appears near the top of the "Top 21 BL motor" article is also a good choice.. Speed Passion also do some motor and ESC combos that offer good performance for a good price..

That last combo that you posted from Horizon Hobby is a NON-Sensored combo... You may also notice that the motor has fins around the stator, and that typically means that the motor has smaller 380 size internals that have been placed in a larger 540 case, and they usually have less torque than a full size 540 motor.. (IMHO, the lower torque makes them a good choice for vintage RC cars as they should put less stress on the older gears, while still giving more speed) 

 

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