As any RC gearheads knows, heat is something that needs to be managed in a vehicle. That’s because electronic performance degrades at higher temperatures, which can cause some of the sensitive and expensive electronic parts inside to fail.

 

Even in cool environments, some components may heat up to the upper limits of operability, so of course drivers have plenty of reason to worry when running vehicles on hot summer days.

 

Overheating

 

Running your vehicle outside on a hot, sunny day is very different from driving inside. 

 

Even though the air temperature may be in the low 90s, the pavement that you are driving on could still be as hot as 120° due to direct sunlight. And the sunlight that’s beating down on the pavement will also be heating up your vehicle, especially if the vehicle body is black or dark-colored.

 

These ambient temperatures should still be well within the operable limits of your electronics. But they will raise the base temperature of components that normally heat up while driving. This combination can push certain electronics past their limits.

 

The good news is that most newer components now have thermal safety overrides built into them, allowing them to simply shut down when they get too hot. This helps protect brushless motors and ESCs (electronic speed control) from being damaged.

 

But while this may help protect your vehicle's most important and expensive parts from damage, it will not help other, lesser components that are not equipped with the same safety feature. It also does not ensure that overheating will not diminish the lifespan of these components over time.

 

The only way to fully protect your vehicle from overheating is to keep it well-tuned and avoid driving it in excessively hot conditions.

 

Electric vs. Nitro

 

Oddly enough, gas-powered RC vehicles generally do better in hot weather than electric ones. That’s because not only are nitro engines designed for higher temperatures, but they can also be tuned to match with weather conditions.

 

Generally, you’ll want to tune a nitro engine to run lean in hot summer weather, and run rich in colder weather. Nitro engines run best when warm, so a rich fuel mix will help a cold engine reach optimal temperatures more quickly, whereas running lean in hot weather will help keep the engine “in the zone.”

 

Unfortunately, electric engines and components don’t have the same kind of thermal adjustment that can be made, so keeping them cool usually relies upon keeping them properly tuned and ventilated.

 

Overgearing

 

One of the easiest ways to overheat your electric engine is by overgearing it. 

 

Often, drivers will do this inadvertently by installing wheels with larger diameters, which throws off the delicate balance between torque and speed and puts a greater strain on the engine and ESC.

 

Other modifications to your drive train can have the same effect, but may be necessary to take your vehicle to its top speeds. So drivers need to consider the ramifications of any tradeoff between speed and efficiency when it comes to operating their vehicles in hot weather.

 

Most electric motors are rated at around 170°F (77°C), so you need to make sure that you keep temperatures below that threshold. Use an infrared thermometer to check after a few minutes of operation. 

 

Keeping Cool

 

Fortunately, there are some things that can be done to help keep your vehicle from overheating.

 

One of the simplest ways to keep your electric motor cooler is to add a heatsink to it. These are readily available, relatively inexpensive, and easy to install. Just be sure to clean the metal surface of your motor, and apply a liberal amount of thermal paste inside the heatsink before clipping it on.

 

Another option is to install a fan. This is usually a little more involved as the fan will need to share power from somewhere in the engine compartment. But you add a fan to your ESC or any other component you wish to keep cool, or use it in combination with a heatsink to cool your engine.

 

Drivers should also consider increasing their vehicle’s ventilation. This usually means cutting additional holes or slots in the vehicle body to allow more air to enter the engine compartment, and more heat to escape it.

 

This can be accomplished without too much difficulty, but it may impact your vehicle’s aesthetics somewhat. Remember that heat management almost always involves some form of trade-off.

 

Another option that drivers should consider is upgrading their engine bearings to full ceramic or ceramic hybrids. Ceramic bearings operate with significantly less friction than conventional bearings, and are virtually unaffected by any level of heat generated by an RC vehicle.

 

Simply by operating more efficiently, ceramic bearings will help reduce the ambient heat that can build up inside your vehicle’s engine compartment on a hot summer day.