Does higher kv mean more speed or not

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djdjdjshsh

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Arrma RC's
  1. Typhon 3s
So I’m confused on how the motors work and the specifications and what they mean, for example I have a typhon 3s and the stock motor is 3200kv 3660 and I was suggested a 2650kv 4068 motor and was told it was faster, but the kv are lower so I wasn’t sure if it was faster or slower or had any clue what specifications mean faster or slower
 
3660 and 4068 are the sizes. So your correct on the same gearing it will be slower but the extra power from the bigger motor means you can gear it up higher than you could with the small motor
 
The kv is the speed at which the motor turns for a given voltage.

So technically, yes, higher kv is "faster"

However, that kv rating is without a load. A 1000kv motor won't be able to spin at 1000kv if the vehicle is too heavy. There is insufficient torque.

Lowering the kv increases the torque available. But you also spin slower for a given voltage. But this ain't a huge issue because you can gear higher to get that speed back.

Does that make sense?

1000kv will spin 1000rpm for every volt you input. Input 10 volts, and it will spin 10,000rpm with no load. If load is too great, you will never reach top rpm.
 
This is a bit of a malformed question to which a simple yes or no answer would not provide any useful information. If your question is, "Will a higher KV motor produce higher speeds at equal voltage" then the answer, all other things being the same, is unequivocally: yes. But if the higher KV motor cannot handle the same voltage as motor A, then the answer is, maybe. Really high KV motors tend to be rather small to keep the inertial mass low and, when choosing a motor, it needs to be matched within certain parameters to the size of your car. There's no point in putting a 7000KV 3660 motor into something like an Infraction as it just won't have sufficient mass to throw around in order to change the inertial state of the vehicle at rest at a rate that would make the car "feel" fast. This is why you typically find motors in the 4074 range in 6S vehicles. While this is a decent sized motor to put some pep in your step, it will run out of breath if you really want to go fast as it won't have sufficient torque to overcome the resistance/load of tall gear ratios that you need for speed running. That's why we get larger motors. High revving motors are more at home at 10th or 12th scale. If you're running larger vehicles, (1/8 or larger) it's better to increase the voltage and drop the KV in larger motors as brushless motors really begin to shine when you apply high voltages to really low KV motors in terms of efficiency. This is why the battery packs in Tesla's have 7233 cells as they typically run nominal voltages in the 350-375V range and, while they might be less than ideal in terms of long haul driving or moving heavy loads, their performance in terms of acceleration is retarded.

There's a balance to be found, a sweet spot which each vehicle is bound to have where voltage, KV and proportional weight of the system are in equilibrium with the transport capsule they're propelling. Depending on where you're at with your car it can make sense to increase the KV of the motor, but that isn't necessarily the best way to a faster car and needs to be considered on a case by case basis.

Sorry that this doesn't answer the question you posed, but I hope this helps put your question into the larger context of motor choice and why KV is far from the primary spec to concern yourself with when it comes to purchasing motors. I tried to keep it succinct...not sure I succeeded. But, there it is. :)
 
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