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Why Is My RC Car Going Slow? How To Fix Slow RC Cars

Why Is My RC Car Going Slow? How To Fix Slow RC Cars

Suppose you have already passed from the beginner stage to a more advanced level in the world of RC cars. In that case, speed will surely be an essential factor in your driving experience. But sometimes, it happens that the RC car slows down its performance in terms of speed. In these moments, we ask ourselves, why is my RC car slower?

The speed degradation of the RC car can be due to several factors:

  • Damaged or incompletely charged batteries.
  • Dirty or damaged motor.
  • Stuck drivetrain.

These are the main reasons for the RC car slowing down, but they are not the only ones.

An RC car in the hand of an advanced or professional pilot should be synonymous with pure speed. But when this is no longer the case, it can be frustrating. We want to give you a solution, so, in this article, we will provide you with all the knowledge you need to solve your RC car speed problems.

rc car with snail

Why Does The RC Car Feel Slow?

The initial advice we can give you is not to be alarmed; this problem can be common with RC cars. It usually happens due to the wear of some of its parts or lack of maintenance. Next, we will review some of the factors that can cause the RC car to lose speed.

  • One of the first factors that cause the vehicle to lose speed is that the battery pack has insufficient charge or the time has come to change it.
  • The motor is dirty or damaged. If the engine is indeed not working, you should stop using it and proceed to replace it. Motor wear is not always due to mechanical failure. If you check that the battery has adequate charge and no jamming in the transmission, the motor most likely has fulfilled its service life.
  • The transmission of the RC can jam. To make a quick check for this fault, remove the pinion from the motor. Then, roll the vehicle on a smooth surface to feel for any brakes or obstructions in the transmission.
  • The vehicle's electrical system is too hot. If this is the problem, just let it cool down.
  • The controller setting may be in training mode. Some speed controls have a training mode that decreases power to 50% of capacity.
  • Use a motor pinion that is smaller, trying to lower the motor load and thus increase acceleration.
  • There may be missing bolts in the vehicle's transmission.
  • Sometimes poor acceleration occurs because there is a bad connection between the material and the motor. It is always good to check the battery and motor connectors and look for worn solder joints.
  • Signs of burns on the resistor or speed control are a sign of damage to those parts.

How To Fix Slow RC Cars?

There are multiple ways to fix the speed problem of RC cars, but we must first find the source of the problem to fix it. Whether your vehicle is slowing down due to mechanical failure or having more acceleration power, we bring you the solutions. Below we will list everything you can do to fix or improve the speed of your RC car.

Change The Battery Of The RC Car

Just by changing the battery for a superior model, you will feel a significant increase in speed. The first point to investigate is which battery pack the RC car uses and what its voltage is.

It is essential to know that there are two main types of batteries:

  • Lithium Polymer (Lipo).
  • Nickel Metal Hydride (NiMH).

The NiMH contains several cells, and each of them has a voltage of 1.2 volts. While Lipo batteries vary in the number of cells, and each of them has 3.4 volts. Many RC pilots prefer this type of battery. Lipo batteries are lighter and have much more power. This data means that if we change from a 2-cell battery to a 3-cell battery, we will be increasing the power by 33%.

But before making this change, the owner of the RC should make sure that the motor and the electrical system can withstand this increase in voltage. What you should never do is to put into the car a battery with a higher voltage than the one indicated by the manufacturer. But it is almost always possible to change a NiMH battery for a Lipo battery; check that the ESC is compatible with this type of battery.

Replacing the Motor of the RC Car

This point is a bit more complex. This change requires us to make some calculations. Suppose our car has a problem of acceleration due to the wear or failure of the engine. In such a case, changing it with a new one is practically the only solution. If our car is fine, and the need to change the engine is not due to a malfunction but desire to gain power, it is necessary to analyze all the alternatives in detail.

Sometimes, a bigger engine is not worth it since we could get the same power by changing the transmission ratio. The best option is to seek the advice of a specialist or directly with the manufacturer.

Reducing The Weight Of The RC Car

This action is a simple way to help the car to perform better. The weight reduction consists of changing some of the plastic or heavier parts for others made of lighter materials such as aluminum or graphite.

What you must take into account is that doing this can have some disadvantages. Aesthetically, the RC car may lose its presence. Additionally, a lighter car may lose traction and stability when cornering and making tight turns. You have to evaluate what you want to do because if there is no traction, there is no point in having a lot of power. The power needs to be supported by the correct weight of the vehicle.

Replacing The RC Car Tires

Several elements of the tires can affect the speed of the RC car. First is the tire profile. Tires that are taller make the car go faster, while larger tires can generate more stress on the engine, and the consequence of this stress is overheating.

The type of tire is another relevant aspect to consider. The improvement in acceleration will depend on whether we are using the correct type of tire for the surface on which the RC will run. What this means is slick tires for road and corrugated tires for rough terrain.

Finally, we must verify that the angle of placement of the tires is correct. To do this job, we will need a camber gauge. All tires must have the exact alignment.

lipo battery for rc car

Will A Lipo Battery Make My Rc Car Faster?

Lipo batteries will make your RC car much faster. Lipo batteries are more potent than NiCD and NiMH batteries. Switching to a Lipo battery sometimes involves changing the motor if the vehicle cannot handle the higher voltage.

Lithium polymer batteries are lighter in weight compared to other batteries. Lipo batteries have a 20% to 30% longer life than NiMH. The only disadvantage is that if the battery is punctured or overheated, it can catch fire. For this reason, experts do not recommend Lipo batteries for beginners.

What Is The Fastest Rc Motor?

One of the most efficient motors in terms of power to speed ratio is the Traxxas 3350R Velineon VXL -3S VXL Brushless Power System. It is a mighty motor for 1/10 scale RC cars. It uses high-temperature neodymium magnets and high-speed ball bearings. These attributes allow it to have great power and, at the same time, to have a long working life.

What Is The Fastest Rc Battery?

Among the fastest Lipo batteries available on the market is the Gens Ace 50C 2S 5000MAH 7.4V Lipo. It has a high capacity combined with a high discharge rate; this gives it power and optimized run time. This battery is perfect for 1/8 and 1/10 scale cars.

A Final Thought On The Speed Problems Of Rc Cars

RC cars provide hours of fun right out of the box. However, not everyone is satisfied with the speed of the vehicle. The exciting thing is that we would only have to give it a few tweaks to enhance this feature that we are so interested in. If we change the battery for a Lipo, improve the tires and lighten the weight a bit, we can get an RC that shoots off like a rocket.