The Risks of Buying A Cheap RC Truck

By Terry Dunn

When you first get into the RC cars and trucks, it's tempting to shop on the less expensive end of the aisle.

It's definitely true that you get what you pay for. But as a noob, it's often difficult to recognize or understand what you sacrifice with a bottom-end model. So let's take a look at one of the least expensive 1/10-scale hobby-grade RC trucks available, the ECX Amp, and analyze the pros and cons of pinching pennies.

Analyzing the Amp

The Amp is a 2-wheel-drive truck that comes pre-built or as a kit. Both versions are priced at $130 and include a radio, battery, and charger. You only need to add 4 AA batteries for the transmitter. The kit version also requires paint for the clear plastic body. Obviously, the pre-built version will get you on the road sooner. But the kit version will jump start your knowledge of how RC cars work. Learn now or learn later. The choice is yours.

I highly recommend choosing a 1/10-scale model for your first RC car. They are large enough that the components are easy to work on. At the same time, these cars and trucks are not so large that replacement parts and hop-ups are prohibitively expensive.

The ECX Amp is one of the least expensive hobby-grade trucks available. What do you sacrifice by going cheap?

Like most modern off-road models, the Amp has a molded plastic chassis, long suspension arms and oil-filled coil-over shocks. I've crashed the truck into a few immovable objects and it has proven to be tough.

The transmission has a gear-type differential. Many racing cars and trucks use limited-slip differentials. While limited-slip diffs allow tuning options, they are also more difficult to assemble and require maintenance. Gear differentials are very tough and work well in most situations. They're definitely the best bet for newcomers.

Chassis Pros

I expect any ready-to-run vehicle at this price point to come equipped with plastic or bronze bushings on all of the rotating parts. Bushings are cheap, but tend to wear out and get sloppy pretty quickly…especially with off-road trucks. The Amp, however, has a complete set of ball bearings. This provides better performance and also helps the truck's speed and handling to remain consistent over time. The tradeoff is that ball bearings require periodic cleaning and oiling. Overall, factory-installed ball bearings are a big plus.

The molded plastic chassis is tough and has long-throw suspension with oil-filled shocks.

When you're just starting out, you'll want to try driving at a lot of different locations. The Amp accommodates this with a set of all-terrain tires. They work quite well on pavement, grass and dirt. The factory suspension setup provides a little bit of understeer…at least on paved surfaces. This is much easier for beginners to control than a vehicle with oversteer (lot of spinouts). If you decide to focus on just off-road or on-road driving, you can probably get better traction with specialty tires. But the stock rubber works well and is a good starting point.

The included tires work well on a variety of surfaces. You can swap to custom tires for the best traction in specific conditions.

The transmission is equipped with a slipper clutch on the spur gear. With a high-performance model, a clutch will help you prevent wheel spin. In this application, the biggest benefit of a clutch is that it helps protect the gears from shock loads when landing from jumps and sudden transitions from forward to reverse. It probably isn't a necessary item, but it should improve the Amp's longevity. Like the ball bearings, the clutch is an unexpected, but appreciated bonus feature on this budget truck.

Chassis Cons

All of the suspension linkages and steering rods are fixed-length, preventing any adjustment of the suspension geometry.

My only gripe with the chassis setup of the Amp is that none of the suspension linkages are adjustable. The steering rods and upper suspension linkages are all fixed-length nylon parts. In one sense, that can be seen as a good thing. With no adjustment options, there is no way for a hapless beginner to foul things up.

Beginner-oriented trucks like the Amp are great hands-on science classrooms.

On the other hand, I've always thought that RC cars are a great tool for kids (and adults) to learn science. Making adjustments to camber and toe-in (one change at a time, of course), and then seeing the performance differences, can be a great hands-on lesson in physics. It would be nice if the Amp included adjustable linkages and a few mounting options to accommodate that spectrum of the beginner's learning curve. On the plus side, upgrading the linkages with adjustable aftermarket parts is a simple and relatively inexpensive project.

Electronics Pros

The Amp comes with a standard "can-style" brushed motor. It may sound counter-intuitive, but I think that the inexpensive brushed motor is a definite advantage here. With beginners at the wheel, having a powerful brushless motor just means that they'll crash into things at a faster speed. A docile brushed motor provides all the power that a rookie needs. I think that new drivers will still find the Amp plenty fast. In fact, I actually reduced the maximum throttle setting when my 8-year-old daughter was driving the Amp (at her request).

Too much power is a bad things for rookie drivers. The Amp's modest and inexpensive brushed motor is a good choice.

A 6-cell 1800mAh NiMH battery is included with the truck. Again, this is relatively old technology, but totally appropriate for RC newcomers. LiPo batteries are lighter and more energy-dense, but they also require very specific handling protocols. Ni-Cad and NiMH chemistries are still completely valid options, and they're much more tolerant of mishandling than LiPo batteries. For what it's worth, I tried fitting a 2S-5000mAh hard-shell LiPo in the Amp. While footprint of the battery fit into the chassis just fine, it was slightly too tall for the clip-in battery retention strap to work.

Another positive feature of the stock battery is that it uses a high-quality power connector called the EC3. Many beginner-oriented models use awful connectors with high electrical resistance that only gets worse with age and wear. EC3s will last a long time and provide good performance.

The transmitter is small but comfortable. It has adjustment options that are good for beginners.

The stock battery provides about 10 minutes of run time. You will probably want additional batteries to lengthen your driving sessions. The stock battery can be had for only $12. Numerous other compatible batteries with greater capacity (i.e. longer run time) are available at various price points.

The radio transmitter that is included with the Amp is deceptively appropriate for beginners. It appears to be very basic…and compared to racing-caliber radios, it is. But the features that it does have are what rookies need. First of all, it is a 2.4GHz system, so you don't have to worry about interference, or conflicting with other drivers. The transmitter also has end-point adjustment (although they call it "dual rate"), which allows you to set how much steering and throttle the truck has. As I found with my daughter, scaling back both controls is a big help for new drivers. The transmitter is physically much smaller than most modern radios, but it is a comfortable grip for me. My 8-year-old did not have any ergonomic problems either.

Electronics Cons

The receiver end of the radio system is actually a combination receiver and Electronic Speed Control (ESC). This isn't necessarily a bad thing. It merely means that both components must be replaced if one of them goes bad or you want to upgrade. My only real issue with the unit is the lack of any published specifications for the ESC side. It would be great to know what built-in features the ESC has. For instance, does it have a low-voltage-cutoff that makes it compatible for use with LiPo batteries? Or is it possible to disable reverse (required at most organized RC racetracks)? I currently have no way of knowing, so I must assume that neither option is present.

The receiver and ESC are combined into a single unit. The lack of ESC documentation makes performance upgrades a trial-and-error affair.

It is possible to improve a vehicle's performance through hotter (brushed) motors, different gearing, or higher-voltage batteries. With any of these approaches, it is very helpful to know the ESC's limitations so that you do not push things too far. Without the manufacturer's specifications, you're just guessing and rolling the dice. To that end, I've run the Amp with a 7-cell NiMH battery. The additional voltage over the stock 6-cell battery provides a noticeable bump in top speed. Neither the motor or ESC is hot at the end of a run. That's an encouraging sign that this upgrade will work long-term. But it's hardly foolproof.

The stock NiMH battery is cheap and resilient, but the included battery charger is way too slow.

The only dud piece of equipment included with the Amp is the battery charger. It works fine but it is really slow…9 hours to charge the stock battery. Nobody wants to wait that long when there are inexpensive chargers that can do the same job in about an hour (even less if you don't mind stressing the battery a little). If you have a couple of spare batteries, it would take more than a day of non-stop charging to prepare for an outing. Considering all of the other practical and user-friendly components included with the Amp, a 9-hour charger just doesn't meet the same standard. You can pick up an infinitely more capable charger for about $30.

Final Tally

When I first got into RC cars, ready-to-run options didn't really exist. Even so, $130 would have barely been enough for a decent chassis kit. Adding a motor, battery, charger, ESC, and radio would have at least doubled the price to get started. Things sure have changed! The Amp is a very capable truck that will serve beginners and backyard bashers well. It isn't the most powerful vehicle around, but that is one of its beginner-friendly charms.

I suppose the foundation is there to modify the Amp into a competitive club-level racer if you really wanted. But it may not make economic sense to do so. I think the Amp is best viewed as a tough, hobby-grade basher to help you learn the ropes of RC cars. With that in mind, we should repeat the initial question, "What do I sacrifice by selecting a bottom-dollar RC truck?" I think the answer is, "Not much."

Terry is a freelance writer living in Lubbock, Texas. Visit his website at TerryDunn.org and follow him on Twitter and Facebook. You can also hear Terry talk about RC hobbies as one of the hosts of the RC Roundtable podcast.