So you want to add a trailer or sled behind your RC to pull some extra weight around. Maybe just because it looks cool or to give the kids a fun ride without using manpower? Whatever your reasons are, it isn’t as much of a novel idea as you may think.
An RC car can pull weight. In simple terms, a heavy RC car with, large grippy tires, a powerful motor, and low gearing can pull more weight than a stock standard RC car. An RC car can pull anywhere from its own weight all the way to 100X its weight in optimal conditions.
How Much Weight Can An RC Car Pull?
The Traxxas XMAXX can pull a vehicle of 2716lbs without even being weighed down. This was achieved in, “ideal circumstances”, meaning the terrain was grippy asphalt with no incline.
Have a quick look at the video before we carry on:
As you can see, he did indeed pull the full-size car with his RC, even though it was slow, struggling, and hopping around a bit, it’s very impressive seeing as how he mentions no modifications added. Even if he just added some weight to the XMAXX it would have made it pull that car much easier.
If he was on the grass though, the XMAXX wouldn’t have moved an inch because the wheels would have no traction and just spin in one spot. It also takes more energy to roll the car on grass than the pavement. We’ll go through all of this in a bit.
So the answer to “how much weight an RC car can pull” really depends on many factors, so let’s go through them and talk about optimizing them for maximum pulling capabilities.
What Influences The Amount Of Weight An RC can Pull?
The amount of weight your RC car can pull depends on many factors, but these are the most important ones:
The downward force on the wheels
If you don’t add any extra weight to the RC itself, you’ll land up spinning and bouncing around not getting very far. Add too much weight and you’ll burn out your motor fast and overload the suspension and tires in the process.
Adding weight to your RC will increase the downward force on the tires. With an increased downward force, there’s an increase in traction between the tires and the terrain.
If the front wheels of your RC are lifting up when trying to pull a load, add some weights to the front end of the car. This will force them down so that they can bite onto the terrain and stand a better chance at pulling extra weight together with the back tires.
You’ll need to add weights to your RC incrementally and observe the effects as you test it. You can get weights like these on Amazon to start off with, they have sticky sides for easy application.
Whenever you add weights to your RC, check the motor temperature with a temp gun after a couple of minutes of driving.
The amount of tire traction
The easiest way to pull more weight with your RC is to increase the traction of the tires. In most cases, if you’re trying to pull something too heavy for your RC to handle, the wheels will land up spinning and hopping up and down as the weight you’re trying to pull overpowers the grip of the tires.
One of the best ways to add traction to your RC tires without adding vehicle weight is to soak them in WD-40 overnight and then rinse them off with water the next morning. WD-40 cleans and softens the rubber to make it more grippy. This technique can be used on all types of tires whether they’re on or off-road.
The type of tires you use
The more contact area there is between the terrain and the tire, the more traction there’ll be. This means that slick tires have the best grip on flat paved surfaces and the bigger they are, the better.
When it comes to pulling weight across the dirt, you’ll need a tread design that can dig through it, like the V-tread design you see on full-size tractors or big wheels with a knobbly tread design.
The terrain
The type of terrain you plan to drive on will impact your pulling capacity. Dirt, pebbles, and grass will decrease your pulling capacity because your tires won’t have much grip on those surfaces.
Asphalt is generally easier to tow on because your tires have a lot of grip on it.
The gearing of your RC
If you plan on pulling heavy objects with your RC, you should have it geared down so that it’s more powerful at lower speeds as opposed to being able to reach high speeds.
The closer the tooth count is of the pinion and spur gear, the higher speeds you’ll get. But what you’re looking for is powerful pulling strength at low speeds, so you’d need to decrease your pinion gear’s tooth count which will increase your low-end torque.
The power of the motor
Generally, a bigger, stronger motor will be able to pull more than a smaller motor. There are some exceptions to the rule but in most cases, you can be sure that upgrading your motor to a stronger one will give you more pulling power.
What’s more important than a strong motor? The gear ratio of course.
Pulling a trailer VS a sled
Pulling something that’s sliding across sand or snow is harder for the RC to handle than pulling a trailer with wheels on it. So if you’re looking for maximum pulling capabilities, pull something with wheels on it.
Install more powerful batteries
Since the batteries are what’s powering the motor, installing more powerful ones will give you more pulling capacity. Ask your dealer which batteries they offer that will provide maximum pulling power.
Check this post out: Will A Lipo Battery Make My RC Car Faster?
How To Build An RC Pulling Truck
Building an RC Pulling Truck involves combining as many of the above factors together.
- Increase the traction of your tires by adding weight to your RC.
- Further increase the tire traction by treating them with WD-40 overnight and then washing them off the next morning.
- Use the right tires for pulling, slicks for dry asphalt, and off-road tires for the dirt. The bigger the tires are, the better, because it equates to more contact area on the terrain and therefore more traction.
- For optimal pulling performance, pull on asphalt.
- Gear your RC down for stronger low-end speeds as opposed to high top-end speeds.
- Install a more powerful motor.
- Pull a trailer with wheels instead of a sled.
- Install more powerful batteries.
RC Pulling Truck Rules
Just like with most competitions, the rules depend on the organizers. With RC pulling truck rules, you’ll mostly find restrictions on the weight, motor, batteries, chassis, tires, body, hitch, and dimensions of the RC. You’ll have to request the specific rules from the event organizer to see what they stipulate for each individual competition.
Of course, if you just doing this for yourself and not to enter into any competition, there are no rules and you can just push everything to the maximum limits.
Conclusion
People want to pull weight with RC cars for a variety of reasons. Some want to give their pets a bit of a joy ride in a trailer, others manage to load their kids in and tow them around the streets.
But people are also serious about pulling with their RC cars and they enter contests to see who can pull the most while abiding by the competition limits.
Either way, by following the advice given throughout this article, you’ll be pulling more weight than ever before in no time.
Keep in mind that by pulling extra weight with your RC car you’ll be putting it under a lot more strain and could damage the parts like the gears, suspension, motor, and more.
Always make small adjustments whenever changing anything on the RC and test to see how it’s performing as you go. When pulling weight, don’t go all out in the beginning, pull a small amount, and increase the weight slowly. You could also buy stronger parts to counter the extra strain especially if you plan on pulling extra weight regularly.
