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How To Cut RC Tire Foam

If you have been using RC cars for any amount of time at all you likely have learned that the tires on an RC car aren’t the same as tires on normal vehicles. One of the main differences between RC tires and normal ones is that RC tires have foam inside of them rather than being filled with air. 

This foam inside the tire is designed to allow your RC car to get better traction when it is off roading while still helping to keep the shape of the tire and for the tire not to be “flat”. 

There are many different ways you can cut your RC tire foam to help get better traction but if you are just going for a traditional RC tire then you actually shouldn’t have to trim the foam at all. Simply put the foam in the tire and then glue the tire to the rim and you are ready to race. 

Some hobbyists prefer to use special designs in their foam inserts to help get more traction than they normally would with the most popular of these designs is the “star”. This design allows you to get much more grip with your RC car which will help when going in especially muddy or sandy terrains where getting traction is always difficult. 

There are other patterns that are used as well such as the pie pattern and even half moon pattern. Both of these are less common than the star pattern mentioned above but will also work to increase the traction of your RC tires. 

Ultimately you will have to decide what pattern you want to use and then begin marking up your foam before cutting. 

For the star pattern you will want to divide the foam into 16 or 32 parts using a marker and then cut out each groove making the “star”. You will then put the foam inside of your RC tire and glue it to the rim as normal. 

How do you get more traction on your RC car?

If you are regularly struggling to get the grip you need when you are using your RC car then you will likely want to find a way to fix that issue. It’s a common problem that many people have but not many people know how to fix it. 

You can cut your tire foam inserts in certain patterns to help increase the grip. You can also change out the tires themselves for ones that are designed for more traction. 

Just like with tires on normal cars the more grooves and tread that RC tires have the better traction they will have as well. If you are having problems with traction when using your RC car the first thing to check is whether the tires need to be replaced or changed for ones with better tread. 

If your tires have plenty of tread and grooves then the next thing that you will want to change to increase the traction is to cut the foam inserts as mentioned above. You can use a variety of different patterns but the start pattern is the one that most people prefer. 

How do you put foam in an RC tire? 

If you are newer to RC cars or you have simply never replaced the tires on your RC car you may be wondering exactly how you put the foam into the RC tires. In most cases the foam is pretty large and seems to be larger than the tire itself so how exactly does it fit? 

Putting foam in your RC tires is actually super simple. As long as you have the right size foam you just have to mold it to put it in the tire and then put the foam and tire back on the rim. 

If the foam is a little bit big that isn’t anything to worry about as you want the foam to be large to make the tire hold its shape properly. If you start cutting away at the foam it will make your tire have more traction when off-roading but will also cause it to not work very well when racing on the track as the tires will be more flat. 

RC tire foam alternatives

If you have an RC car and you are tired of constantly having to replace the foam or dry it out when you go through wet terrain then you will likely want to know if there are any alternatives to using foam in your RC tires. Surprisingly there are actually multiple other products that you can use instead of foam which we will cover next. 

Air filled tires 

This is the most common thing to go to when you are tired of using foam and that is to have air filled tires. Using this process is relatively simple to do as all you have to do is plug up the vent holes in your rims and tires and then seal up the tire with glue. You won’t fill your RC tires with an air pump as you would normal car tires as you don’t want them to have much pressure or the glue or tire will give way while racing. 

Instead you will simply let the air around you get into the tire and then once it’s sealed it will stay at that same air capacity while you race it. 

Smaller tires

So this is an odd one but something that many people have reported as working well in some cases and not at all in others. Instead of putting foam inside your RC tire you will put other smaller RC tires! 

Using this alternative you never have to worry about the tire breaking down because of water like foam will since you basically just have rubber inside of a rubber tire. This will likely allow your RC tire to last much longer while you won’t have to replace the foam since there isn’t any. 

Many people who try this method have reported that it works great for RC crawlers as well as off-road racing but not very good for use on tracks so depending on how you plan on using your RC car will determine whether this is a good option for you. 

There are many other things that people have tried including pool noodles, 3D printed inserts, door/window foam, flip flops, and many more. How well some of these will work is pretty suspect but some people swear by their “invention” whether out of pride or because they actually work it’s hard to tell. 


The foam inside your RC tires is honestly a tricky subject but if you are trying to get more traction or grip with your RC car then you will likely want to cut your foam inserts into the star shape to reach that end. You can also go for other types of foam as some are designed to provide more traction while others are made to be used on tracks. 

Whether you choose a foam or one of the many alternatives that people have tried it is always important that you take care of your RC tires to help them last as long as possible.