How to Make your RC Car Faster Pt.1: Upgrading the Motor

    There comes a time in every RC car owners life that you feel what you have isn't fast or powerful enough. You want more speed and you know it! So we started this new series on how to turn your bone stock and sluggish RC car into a speed demon, scratch that, a speed demon's worst nightmare. Are you ready? Well let's get started.

                              Upgrading the Motor

    When you first think about upgrading your RC car the motor is probably the first thing that comes to your mind. There are a few things you'll need to know before you pick your new motor. 

Brushed vs Brushless
    You will see two types of motors when looking, they are brushed and brushless. We won't go into detail on what this means today (we will in a more advanced motor guide). Basically a brushless motor makes more power and has hardly any parts that will wear out, and if they do wear out you can change the internal parts. Whereas the brushed motor has more parts that are more likely to wear out, and once something internal is ruined you can't replace the parts. Pretty much all brushed motors are cheaper than brushless that's why they are what most RC cars come with. In short, if you want a nice powerful RC car don't get what you'll find in a stock RC car, get brushless.
    
What does KV mean?
    So first let's talk about KV. KV is how the motor's power is rated, like horsepower is for cars. It stands for RPM (revolutions per minute) per volt. What that means is that for every volt of power the motor is given, it will turn that many RPM (revolutions per minute) more. So for example, if you have a 7,000 KV motor and give it 5 volts of power then your motor will be spinning at (7 x 5 = 35) 35,000 RPM. Well okay, now you know what KV means but what's faster more or less KV? Good question. The higher KV you have the more top speed get but with less torque. The lower the KV the more torque and acceleration you get but with a lower top speed.

What does Turns mean?
    Now let's talk about turns. Turns are another thing you'll encounter when choosing a better motor. They are another way of rating the motor's power. Turns are abbreviated with the letter 'T'. The number of turns a motor has is how many times the copper wire is wound around each pole of the armature inside the motor (don't worry you don't have to understand). With lower turns you get a higher KV and less torque. With higher turns you get lower KV and more torque. Here is a simple way for you to look at it:

Less KV/More Turns = Higher torque (acceleration), less rpm (top speed), and longer battery life.
Higher KV/Less Turns = Less torque (acceleration), more rpm (top speed), and shorter battery life.

Sensored vs Sensorless 
    Sensored motors have a little port on the back for connecting the motor to the ESC (Electronic Speed Control). The reason they connect is so that the ESC can monitor the position of the rotor and deliver the power to the motor smoothly. You really only notice this when you first punch the gas, once you get up in the higher RPM range it doesn't matter much. Sensored motors require a sensored ESC to go along with it. The price difference between a sensored motor and sensorless motor (regular motor) is about $20-$30. It may or may not be worth it to you depending on your budget. You can check out the link below and look at the related products on Amazon to get a feel for the price and what you can afford.
Hobbypower 10 turn, 3900kv, Brushless Motor for 1/10 Rc Car or Truck
Making sure it fits
    Making sure your motor fits is obviously very important! Your going to want to look for the length, diameter, and shaft width of the motor. The shaft width is how wide the piece that the pinion gear (the pinion gear is the small gear on the tip of your motor shaft, the large one is the spur gear) will go on. Make sure it's not some crazy size your pinion gear can't fit on. You'll also wan't to look at the motor's spacing of the mounting holes so it will fit on your mount.

Don't forget to upgrade your ESC too!
The ESC (Electronic Speed Control) is the mediator between the battery power and your motor. It's like the negotiator almost. It connects to the receiver and gets the signals from your remote telling it how much power it should release. So for all the power to be able to go through and reach the motor, the ESC must be able to handle it without getting fried. So when you upgrade your motor you will have to upgrade your ESC as well. You will need to look at your selected motor's wattage, max amps, and continuous amps. Then find an ESC that is a little better than what you need, just in case. For example: my motor has a continuous current of 150A (Amps) so it would be smart to get an ESC that can handle 170A or more. But don't stress to much over this because most websites and stores will tell you what ESC you need.

What's next?
So now you know everything you need to about upgrading your RC car's motor. What's after that? Well the next thing we'll talk about in our series is the battery. So stay tuned folks!
    

7 comments:

  1. wowww thanku keep updating and also tell something about rc helicopter

    ReplyDelete
  2. I'm glad you like the post and thanks for the suggestion Anvesh! If there is anything particular you would like in a post on RC Helicopters let me know!

    ReplyDelete
  3. Thnx keep updatn

    ReplyDelete
    Replies
    1. Thank you so much for the info on batteries.....motor and reciever..
      I wanted to ask about the wheel base....and how to choose the servo.....i want a little room for future additions ....like attaching an arduino circuit.....

      Delete
  4. thank you very much, i like your article
    it can help me
    Rc airplane

    ReplyDelete
  5. thanks for useful information, but this is a bit confused. The key thing to ultimate performance is power: voltage is not power. Power is what you referred to later on as 'wattage'. A 2000kV motor with a max power output of 20W is not going to be useful for anything... it will only work when unloaded. A 2000kV motor with a power output of 3000W is a beast. It is NOT true that KV is the equivalent of hp in a car. In fact hp is exactly the same for RC and real cars.. about 750W is one horsepower. You need horsepower for both top end speed and also for acceleration. Then the KV rating can be chosen according to whether you are aiming at low speed torque or high top end speed.

    ReplyDelete
  6. nice post, keep up with this interesting work. It really is good to know that this topic is being covered also on this web site so cheers for taking time to discuss this! bmw330d

    ReplyDelete

Need help or have a comment? Just type!

ShareThis