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What Are Foam RC Tires For?

If you have ever looked closely at the tires of your RC car or simply pressed on them you likely have realized that they aren’t filled with air like traditional car tires. This might come as a surprise to some people but most RC car tires are actually filled with foam! 

You might be wondering what the reason behind this is. Why not simply use air instead? 

Foam inserts are used in RC tires to give them stability and grip. Having air filled RC tires would cause issues by not having enough give or by getting punctured regularly which is why most RC vehicles have foam tires. 

Without the foam inside the tires they would quickly become deformed and would not allow the RC vehicle to drive very smoothly so that is why something is used inside the RC tires. 

Many people who haven’t had Rc vehicles think that having an air filled tire would make more sense however often RC vehicles will be driving off road or over sharp or pointy obstacles which can cause the tires to get punctured and go flat. Also if you use your RC vehicle on jumps or even get it airborne accidentally when it lands it can often pop the tires right off the rim if they are filled with air rather than simply being foam tires. 

Because of these and other reasons foam inserts are favored when compared to pressurized air. The reason for this is all about the RC tire construction. The uneven tire construction, compared with air can be a disastrous experience. 

Usually, normal tires on a regular car are reinforced with steel wires, rubber, and many chemicals. All these elements help to hold the air in place inside the tire in a way that the pressure is distributed uniformly over the inner tire. 

RC tires, however, lack this luxury, i.e, RC tires are not reinforced. If you happened to use air in these tires, there would be uneven pressure, and the tires would expand disproportionately. This can even cause the car to flip over or could cause your RC vehicle to roll right off the track. Besides, small, air-filled tires cannot be mended in situations like a flat tire.

However, with foam inserts, you can avoid this problem altogether and with foam tires you can easily power through the rockiest of situations and your RC vehicle will come out without a problem. 

Foam inserts are the next best alternatives to air pressured wheels and are really the only solution for RC car tires. 

For convenience, there are different types of foam inserts that you can choose from. Each foam insert has a purpose of its own so make sure to select the one that will match what you need to do with your RC vehicle. 

Types of foam inserts

There are three basic types of foam inserts. These are:

1. Normal/regular foam inserts

Normal foam inserts are the cheapest ones you’ll find. They are square cornered and flat-faced on all sides. They are very “normal”, in a way that there is nothing that makes these inserts special in any way. They typically don’t contribute much in terms of performance to a car.

2. Dual-stage foam inserts

The explanation behind these tires is in its name itself. Dual-stage foam inserts, unlike regular foam inserts, have strong foam forming on the inner half and a softer foam coating on the outer half. This design can also be interchangeable, i.e, soft foam outside and firm foam coating on the inner half. However, the first design is found more commonly. 

These inserts are also square-cornered and display a flat face on the outside. However, it is their dynamic design of dual layers that bought them the name.

3. Molded foam inserts

Molded foam inserts are possibly the most expensive option among the three. These inserts are basically “molded”, to emulate the shape of the inner tires. They have a structurally curved outer face, curved sidewalls, and a curved inner face. These features help them to comfortably adjust on the rim and inside the tires.

How do these RC foam inserts function?

All three of the foam inserts mentioned above can be separated not only based on their structural differences but also based on the functions they provide. It is these functions, which are of utmost importance to consider while making a foam insert purchase. 

With an RC car, you might have the desire to drive them across the wildest places. You might want to cruise over rough patches or smooth pavement and to help you achieve that dream, you have to choose between different foam inserts that offer different advantages.

As you already know, most RC cars come with regular foam inserts themselves. However, if you want your car to perform better, you might have to change out the regular insert for something better. This is where their differences come into play. You can take into account the different factors that make each of them unique and make a decision based on that. 


The width of your tire inserts can more or less determine the stability of your vehicle. Wide inserts have more benefits as compared to normal ones because the wide ones project a firm grip onto the tire sidewalks to maintain shape and integrity. With this feature, you can take on sharp and rough corners with ease. 

However, if drifting and cruising is more your cup of tea, molded inserts are your best bet. Molded foam inserts firmly hold the entire inner tire in place and deliver good results.


With firmness, it is almost always a give-and-take relationship. Firm inserts offer good support during rough activities like turning corners and so on. However, firm inserts often cannot absorb shockwaves emerging from rough surfaces or jumps. Thus, firm inserts are far more suitable for smooth and uninterrupted roads.

Thus, firm inserts are not the go-to for rough patches of roads, as these two are highly incompatible. A firm insert on a bumpy road can have some negative consequences as the RC car will be very unstable and you might end up losing some important internal components. 

To deal with roads like these, a new foam insert can be introduced- the dual-stage inserts!

The dual-stage inserts are two-layered and hence provide all around protection to the RC tire. The inner foam coating lets you surf past corners flawlessly while the soft outer layer deals with the shocks from the ground. Thus, owning a dual insert means that you can use your RC vehicle in rough terrain all you want without the need for worry.

The molded foam insert is also a remarkable foam insert you can use in your Rc vehicle’s tires. Firstly, it is made up of reusable material that does not break them. Molded foam inserts can take any shape that you want. 

Thus, they can sit snugly against the face of the tire and its rim. 

Molded foam inserts are special because they are the only foam inserts that can help do away completely with uneven pressure points in an RC tire. Thus, a car can now work completely without breaking into parts.

Fitting the rim

While looking for a comfortable foam insert, make sure to find one that fits well on the rim. A good foam insert should be flexible enough to envelop the rim tightly. This will prevent the foam insert inside from moving around and bouncing. Check the inner diameter of the foam to the outer diameter of the rim to see if the foam insert is good enough for your RC car. The molded Foam Insert is especially useful in satisfying this factor.


Foam tires, thus, can potentially outlast any other inserts or tires with features like this. Fill your RC tire up with the brim and watch your vehicle excel on uneven and uniform ground while taking care to keep your RC car damage free.