Brushless Motor and ESC

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Brushless Motor and ESC

Darren Wes

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Be gentel when you start using the brushless so you don't break gears or strain anything too hard

Esc

http://www.amazon.com/gp/aw/d/B00DU...ds=60a+esc&dpPl=1&dpID=512UnXZjt2L&ref=plSrch

Motor

http://www.amazon.com/dp/B00GV5YX6U/ref=sr_ph?ie=UTF8&qid=1432444866&sr=1&keywords=3900kv+brushless

I used this setup with an onyx 5000mah 2s 25c tonight and walked for a whole hour about 1 mile drove maybe 2 miles. I was going about 20-40% throttle for about 60% of the ride and the rest was spent on the grass... poping wheelies (its a bit tricky but possible on 2s)... and full throttle. Very satisfied for about $40-50. At the end of the run i was at about 150-160degrees

I would suggest a either the onyx i have or maybe even a smaller lipo.... i also got and hour run out of a 2000mah though i stayed under 60% throttle the whole time ...maybe a 4000mah soft case would be a nice give and take on weight and not giving up a big amount of battery storage... you could do 30c with a 2s but your temps will rise faster. But you will probably have a little bit easier time doing wheelies , if you don't want to try your luck at 3s.

I got a new 4000mah 3s lipo 20c in the mail gonna try my luck on the real streets!
 

roger nelson

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Those hobbypower combos are really priced right! Anybody know what kv the titan12t is? I'm gonna run a nexus 45c/90burst liPo in the fury today. Is that crazy or just a ok thing.
 

Darren Wes

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Ive heard its the same thing just with leopard on the side.
Not sure if that's true. .. Its the affordable route you will want to upgrade if you want to do much more then 2s with the occasional 3s
did you try Hobby Wing products too...they are 100% same thing and about 20/30bucks less then leopard
Here is another amazon link to a different company selling the same thing
http://www.amazon.com/dp/B00KKY9GQA/

70 and 120 (cost of a bottom tier quality brushless system) are pretty close... I would almost go for the viper system...

But the fact that the motor is completely red is intriguing. I am kinda turned off by my purple motor out the back...but whatever you do it'll fly regardless
 

Unusual RC

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Is a 4 poles 12T 3300KV Brushless Motor too much power for the Fury?, this would be combined with a 60A Brushless ESC. Iwould like your thoughts about the combo.

A four pole motor comes in BLX power territory.
This means relatively less rpm but more torque. So you need to change gearing to something like 11/57 or 13/57 32p/0.8
Default mega gearing is 17/87 48p. The stock 15T brushed motor is 20000rpm / 7,4v = 2700kV

That is simplified comparable with a 2 pole 45amp brushless set. So even the BLS 4000kV will give you much more speed and power on stock gearing.

You can order the BLX spur gear, and i would recommend the traxxas motor pinions since those from Arrma are hard to get.
Please be aware the default slipper pads are glued in.
When you go for another spurgear you need to order those too!
 

Darren Wes

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Is a 4 poles 12T 3300KV Brushless Motor too much power for the Fury?, this would be combined with a 60A Brushless ESC. Iwould like your thoughts about the combo.

yes it will work, and 3s will be awesome just make sure your battery doesn't have to high of a c-rating... the small esc wont like anything prolly over 25c from a 3s
 

Darren Wes

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A four pole motor comes in BLX power territory.
This means relatively less rpm but more torque. So you need to change gearing to something like 11/57 or 13/57 32p/0.8
Default mega gearing is 17/87 48p. The stock 15T brushed motor is 20000rpm / 7,4v = 2700kV

That is simplified comparable with a 2 pole 45amp brushless set. So even the BLS 4000kV will give you much more speed and power on stock gearing.

You can order the BLX spur gear, and i would recommend the traxxas motor pinions since those from Arrma are hard to get.
Please be aware the default slipper pads are glued in.
When you go for another spurgear you need to order those too!
I foget what is larger 32p or 48p? I think 32 but i cant remeber
 

Darren Wes

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4370 will be faster. i go about 30ish (accutally haven't tested 2s top speed yet) mph with a granite on a 3900kv motor and stock gears but it gets hot when i run it hard after 10 min...

i could see yours going A solid 34mph ish on 2s with stock gears and that 4370...you would also have semi long runtimes. I don't think you will lave too many heat issues unless your trying to race instead of bash

jumps offroading and speed runs combined with accelrated turns burning rubber and wheelies i only get about 20-25min before i decide im probably gonna destroy it if i keep going. Even though i was only at 160 degrees. I find that to be too hot to drive on for longer periods then 5 more min.

If i were you and i was upgrading the drivetrain again on budget i would go with somthing like the 3300kv hobbybrand and run it on 3s only... also i would get a 20c 3400ish mah 3s and maybe chage a gear...maybe... may not go "faster" but the punch from the 3s will sure make it seem faster....

In the end its what you want... i wanted long runtimes and versiatility with a focus of top speeds because i typically drive on roads. So i choose the 39 because i can run 2s well with a little more speed without loosing much torque... could have choose somthing like the 4300kv+ but i wanted to try 3s somtimes... i would have choose a 3600KV but i wanted to smoke some vxls... i would have choosen the 2900-3300if i were driving on grass a bunch, but i don't. And finally brings me to the 2200-2600kv which would be the fastest because you can find more motors that will accept 4s...which is where i wabt to take my granite eventually
 

Darren Wes

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If all you will run is nihm you will just have to decide less speed and more runtime or more speed and less runtime. I would go with the 4370. because brushless are more efficient overall so theoreticly speaking it should level out your runtimes tho u are adding more power.... and if your battery bites the dust you can decide between a nihm with more mah or a lipo about the same mah as the original
 

Darren Wes

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Unusual RC

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I foget what is larger 32p or 48p? I think 32 but i cant remeber

32p has bigger teeth, which means less teeth on the same diameter of gear as the stock 48p.
Only gears with this same ratio will go well together.

The problem with brushless motors is the comparison between them.
There is no uniform system.
Rpm per volt (kV), windings (T) and the number of poles (2 vs 4) does not say all.

Sensor or sensorless is also a factor. Sensored are in general more efficient thus give more power than an equal sensorless system.

Then windings does not say all. Also wire diameter of those wires, the way they are wound (quality wise) make the motor more or less efficient.

Also can length, which says something of the size of magnets on the rotor, and the size of the wounded coils. The bigger, the more torque in general.

But you also have different quality magnets. Neodymium are one of the strongest permanent magnets out there.

And then amperage use. With the volt number (2S, 3S), motor efficiency in percent, and the maximum ampere usage you can calculate the maximum power output...

But then the gearing comes, which can make or brake the set-up in your RC car.

En then how is this maximum current set? There is no standardized benchmark unfortunately.

Most manufacturers leave out this info, so it is hard to say.

If they offer it as a combo, the maximum amperage of the Esc. can be an indication how powerful the motor might be.
For example, if you connect a motor to a 45Amp esc, which draws maximum 65A, the esc. will cut-off the power to prevent damage. So the set-up will not work.

So if they sell a 60A combo, you may expect it to draw less then 60A when geared properly in your car.

But again, this is never a guarantee!

Sorry I have no simple answer, this is the way it is at the moment :(
 

Darren Wes

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That will be great information when i decide to go 3s all the time. For now im on 2s and i find to have plenty speed and torque with heat in mind. But before the summer ends i hope to have my arrma granite as a 3s.
 

Unusual RC

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Sorry Roger,

In the "brushed era" it was much easier to compare one motor with another.

But with brushless and lipo power it became much more complex.

Hopefully people can share their personal pick here with us, including gear info. This can help future MEGA upgraders
 

Darren Wes

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Thats the one im currently using if you like i can run a speed test with my nihm tomorrow and tell you top speed on a granite with basic gears with the 60a esc. I get about 20-25min runtime from the stock arrma 2000mah but the flipside is i usually don't feel like im gonna break anything by hitting the throttle down
I got a 18-20min ride on pavement and doing jumps. out of stock gears a 3900kv brushless with 60a esc after the run i was at 120-130degrees going back and forth at top speed on a stock arrma 2000mah nihm top speed was 27mph like it was fresh outta the box. I will try a 2s lipo later for a compasison (wont be much differnce tho except runtime from a 5000mah)
 

mrbelloso

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By reading here and in other forums the best combo to get would be a 3900KV motor with a 60A ESC so I can still use the gears in my Mega.
 
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