what brushless is right

[Barnfind]

Im sure you guys have probably been asked this several times before and im sorry if it has but my searches on here didn't reveal much. So anyways I am looking for a good brushless combo for the sc10.2 that will be good for racing yet controllable. Also I have never used Brushless or lipo and have no clue what all the numbers and all that mean. I was looking at the castle mamba max combo and as this will be a sponsored buy money is not an issue so any ideas you guys have please feel free to tell me I could use the help being a noob at all this.

[Sixtysixdeuce]

Well, there's quite a bit to it for explaining in a single post.

Brushless motors. There are basically two types; sensored or sensorless. With a sensored motor, there is a hall-effect type sensor that tells the ESC what position the rotor is in so that it knows which coil to pulse. Sensorless systems use EM feedback to determine rotor position; sometimes they spin backwards ever so briefly before the ESC corrects the sequence. So, sensored motors will have smoother, faster starts and smoother low-speed operation

Brushless motors may be rated in turns (just as brushed), or in KV. KV is how fast the motor will free spin (no load) per volt applied. So a 3,000 KV motor on 2S LiPo (8.4V fully charged) would theoretically free spin at 25,200 RPM. Generally speaking, lower KV=higher turn motor, but there is no accurate conversion for determining turns by KV rating or vice-versa.

Lastly, there are 2, 4 and 6 pole brushless motors in the RC world. Most 1/10 stuff is 2 pole, until you move into short course motors. 1/8 motors will almost always be 4 pole, sometimes even 6. More poles=more torque.

To determine which motor you want for racing, you need to first know your class regulations. In 1/10 scale, it is generally, 17.5 turn max for stock and 13.5 turn for modified, but club level will vary. Our local track has a modified class that is simply any 5-series motor, including the torque monster 4-pole 550 series SCT motors.

Lipo batteries. The big difference with LiPo is the discharge capability over NiMH. Brushless motors can demand a lot of power, and LiPo batteries can accomodate. But the ratings do matter.

-Number of cells; just like NiCd, NiMIH or Pb, the number of cells in a LiPo determine the voltage. Each cell is stadard rated at 3.7V, will be 4.2V fully charges. So 2S is 7.4V, 3S is 11.1V, 4S is 14.8V and so on. 1/10 scale is usually limited to 2S LiPo/6 cell NiMH.

-mAh is just that; the battery's capacity to store power. This rating is universal for all power cells and batteries, though it generally becomes Amp-hour instead of milliamp-hour when you eclipse 10,000 mAh; car batteries are rated in amp-hour.

-Discharge rating. This is important. The discharge rating is expressed as a value of "C", and is a function of how much of the battery's stored power can be discharged at a time. 1 "C" is equal to the batter mAh rating, so on a 5,000 mAh pack, 1 C would be 5 amps. So a 5,000 mAh pack with a 25-50C rating can constantly discharge 125 amps, and burst discharge 250 amps. As such, a smaller pack with the same C rating has less discharge capacity, and a larger mAh pack with the same rating can discharge more amps. If your ESC & motor can draw more than the battery is capable of putting out, the capacitors are working overtime and will cook. This is why brushless ESCs have a low voltage cut-off, to prevent battery damage when the pack can no longer keep up with demand.

Speed controllers. Lots to choose from, and they need to be matched to the motor and battery. All of them have a continuous and burst rating, and it needs to be enough to keep up with your other components, or you will let the smoke out. Personally, I like to have quite a margin; If I expect to run 3S and draw bursts of up to 450A, I want a 4S rated ESC that can handle a 700+A burst. Many ESCs will also tell you not only voltage and amperage ratings, but also minimum # of motor turns at a given voltage for on road and for off road use.

Hope that gives you a little bit of an understanding.

Now, as for recommendations. Since it ain't your dime, I don't see why you'd go with anything other than a Tekin RS combo.

[RC10th]

I swear by the Hobbywing V3.1 and whatever motor fits into your class. The V3.1 really shines when you start introducing dynamic timing, but also seems to have more power in blinky classes. It also has the smoothest power delivery of any ESC that I've tried. I have always sworn by the more power thing and everyone else says "yeah yeah" Needless to say a friend bought one and was blown away, he liked it so much he bought another.

The good thing about the ESC when using hobbywing motors is you can data log max RPM and max ESC/Motor temperature. Our class is 10.5 restricted any my T4.2 pulls everyone else down the straight.


Them's my 2 cents...