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what does kv stand for in brushless motors?

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Old 10-04-2008, 07:18 PM
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bruce5385
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Default what does kv stand for in brushless motors?

what do the kv stand for? want to put the brushless losi and dont know what to choose. please help.
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Old 10-04-2008, 07:21 PM
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Frozen72
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Default RE: what does kv stand for in brushless motors?

rpm per volt
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Old 10-04-2008, 07:27 PM
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Default RE: what does kv stand for in brushless motors?

RPM/volt. If you have a 6000kV motor with a 7.4 pack (assuming the rated voltage actually makes it to the motor), you'd potentially have 44,400rpm at the motor.
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Old 10-04-2008, 07:50 PM
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bruce5385
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Default RE: what does kv stand for in brushless motors?

so i should put the 1/18 Xcelorin 9400Kv Brushless Combo in my mini late model because that is the combo that has the most rpm which make the car faster
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Old 10-04-2008, 08:06 PM
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madweazl
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Default RE: what does kv stand for in brushless motors?

Potentially. Higher RPM motors tend to generate less torque, to get within a usable power band you have to gear down which compromises some of that RPM. My preference is higher torque motors that are geared up for better top end. For all out speed runs the higher kV setup would be the best bet. Typically, something in the middle will provide the best driveability.
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Old 10-04-2008, 08:18 PM
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emaXXman123
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Default RE: what does kv stand for in brushless motors?

i'd get between a 7000-6000 Kv motor..i suggest the novak mongoose sensored model
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Old 10-05-2008, 03:29 AM
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Default RE: what does kv stand for in brushless motors?

It might confuse you more than help you but have a play with the numbers in the RC Car/Truck Power & Setup Calculator (rough estimator) to see how the variables interact by changing them.

For 1/18 scale trucks that weight ~600g I prefer 3s on 11.1v ~5000Kv motors geared for 35mph, for streeet bashing it delivers a good compromise for action, run time, cool running, component life span, cost and usable top speed.

You might see a few 2s setups running crazy high Kv motors, I think that's because they might be chasing tall top speeds when operating with lower voltages the high Kv helps to avoid running out of max pinion size head room. Also the higher power 2s setups waste a lot of energy as heat, drawing too many Amps and give 2s packs a harder shorter life.
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Old 10-05-2008, 08:33 AM
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Default RE: what does kv stand for in brushless motors?

To answer the original question- Kv= Kilivolt.
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Old 10-05-2008, 10:04 AM
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Default RE: what does kv stand for in brushless motors?

i want to have low end to hight end and run 7.2 volt nimh batteries for now then switch up to lipo but what is the best brushless motor/combo for this to happen? everyone keeps saying the mid range kv motors but i would think the higher kv motor because you dont have to use all the power the motor provides but if you want it it is there.
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Old 10-05-2008, 04:05 PM
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Default RE: what does kv stand for in brushless motors?


ORIGINAL: bruce5385

i want to have low end to hight end and run 7.2 volt nimh batteries for now then switch up to lipo but what is the best brushless motor/combo for this to happen? everyone keeps saying the mid range kv motors but i would think the higher kv motor because you dont have to use all the power the motor provides but if you want it it is there.
yes, but the higher kv motor also has less torque wich means you would have to change the gearing to get the torque you want, thus sacrificing top end. A mid kv motor is always a good choice because it can be geared for normal driving, extreme torque, or extreme speed very easily.
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Old 10-05-2008, 05:27 PM
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Default RE: what does kv stand for in brushless motors?

wow , what a great place to learn about kv ..
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Old 10-05-2008, 08:38 PM
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Default RE: what does kv stand for in brushless motors?

here's the run down:
High KV:
huge amp draw
has to be geared down (looses revs)
have to be a HAWK on the temps so it doesn't overheat
sucks packs down real quick
it is extreeeemely fast though

Low KV:
lower amp draw
you can gear up and keep temps down
don't have to be a hawk on the temps
keeps packs goin nice and long
it is slower than the higher KV systems but the torque can be insane

I have a 4800 KV motor for my RC18T, i had a CM-20 6800 motor (sidewinder micro with 6800) had nothing but temp problems galore, so i got the 4800 kV, more than enough torque on a 3s, speeds insane, NO HEAT after tons of speed runs on 3s (barely ran the 6800 without tons of heat), plus lower KV motors have less "cogging" and are easier to drive since they are less "rough" on the throttle, just me, and my take on it all, also higher KV motors are better for strictly on-road cars, lower KV is better for off-roaders[8D]
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Old 10-05-2008, 09:28 PM
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Default RE: what does kv stand for in brushless motors?

similar question wat do the turns mean on brushed motors
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Old 10-05-2008, 10:21 PM
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Default RE: what does kv stand for in brushless motors?


ORIGINAL: nitrosport963

similar question wat do the turns mean on brushed motors
The low turn = high rpm low torque
high turn = low rpm high torque

I think its the amount of times they wrap wire around the armature or something like that.
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Old 10-05-2008, 10:21 PM
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Default RE: what does kv stand for in brushless motors?

iv read all this stuff before although when I answere I always get stomped on by sombody that knows too much lol
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Old 10-06-2008, 01:08 AM
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Default RE: what does kv stand for in brushless motors?


ORIGINAL: Mr. Mugen

To answer the original question- Kv= Kilivolt.
The question was answerd in the first reply. When talking about brushless motors, KV does NOT mean kilivolt, it means "RPM per Volt" (if it meant kilivolt, then when you asked for a 6000KV motor, they would hand you a 6,000,000 volt motor.... I dont think most RC cars have room for a 1621621S1P Pack....)
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Old 03-04-2016, 09:17 AM
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Default

The "k" stands for `konstant` - The german word for `constant`
The "V" stands for `velocity`

The correct unit expression is K[SUB]V
[/SUB]

Last edited by brummle; 03-04-2016 at 09:20 AM.
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