1/4-scale electric 4wd buggy | RTR
PHOTOS PETER HALL
Duratrax gives you a lot of buggy for a little cash with this well-equipped RTR
Quick! Name all the electric 1/4-powered buggies available for under $400. There's the, uh … OK, not many. Or maybe none. None except the Duratrax 835E, that is. This buggy features a 2.4GHz radio system, full-time 4WD (with hardened-steel gears, no less), big-bore aluminum shocks, and a 4S-capable brushless system—all for $399.99 (hey, we didn't say it was way under $400, just “under.”) For your four Franklins, Duratrax ticks a lot of boxes on the spec sheet, but quality and performance matter too — even more than price. So let's get to it and see exactly how much bang we're getting for the buck.
Item no.: DTXD78
Weight, as tested: 8 lb., 6.5 oz. (3810g)
Type: 3.25mm aluminum plate
Type: Lower H-arm with turnbuckle camber link
Inboard camber link positions (F/R): 4/4
Outboard camber-link positions (F/R): 4/4
Shock positions, towers (F/R): ⅚
Shock positions, arms (F/R): 2/2
Bodies: Threaded aluminum, 16mm bore
Shafts: 3.5mm steel, chrome plated with bellows shaft cover
Volume compensation: Bladder
Type/ratio: Shaft-driven 4WD with center differential, 3.4:1
Spur gear/pinion: 46T/16T 32 pitch
Slipper clutch: None
Differentials: Bevel gear, silicone filled
Driveshafts: Universal-joint (front), dogbone (rear)
Bearings: Rubber-sealed ball
WHEELS & TIRES
Wheels: One-piece dish, standard 1/4 buggy configuration, 17mm hex
Tires: Duratrax mini-knob
Inserts: Closed-cell foam
Transmitter: Duratrax T240FS 2.4GHz 2-channel
Receiver: Duratrax R240FS 2.4GHz 3-channel
Speed control: Duratrax Onyx 120A, 4S (14.8V) max
Motor: Duratrax Onyx 2200Kv
Steering servo: Duratrax SX501 Waterproof, metal gear
POWERED BY ONYX
The chunky Onyx speed control is fan-cooled, fully adjustable, and provided reliable performance throughout testing.
At the 835E's price point, you would expect (and could excuse) a bare-bones power system, but the supplied Onyx brushless power system is very well featured. Adjustments include drag brake percentage, punch, initial and maximum brake force, deadband, and motor timing. You'll have to count LED flashers to do the programming, which certainly works but is tedious. Instead, I suggest you spend another $15 and get the Duratrax Onyx Programming Card, which makes it much easier to adjust the speed control. The included 2200Kv motor is a 4-pole sensorless unit of simple design, but it does provide ample torque. The more volts the better, and while a battery is not included, the 835E is ready for anything you've got up to a 4S LiPo. If you go for the full 4S option, you'll see top speeds of 40–42mph. On 3S, subtract 10mph.
STEEL-GEAR 4WD SYSTEM
That motor plate isn't going anywhere! The center differential is sealed and filled with silicone fluid, as are the front and rear diffs. Hardened-steel gears are present throughout, too.
No surprise in the suspension department, just time- and track-tested technology here. Turnbuckles and plenty of camber-link position options make it easy to tweak the 835E's handling.
Duratrax spec'd out a very nice drivetrain for the 835E, with details that belie its $400 price tag. The ring, pinion, and spur gear are all solid steel, and the diffs feature helical teeth instead of straight-cut bevel gears. The diffs are sealed and silicone-filled like all modern buggies, and they reach out to the wheels via universal-joint shafts up front and dogbones in the rear. Dogbones also join the front and rear differentials to the center diff. These don't push the cool-parts button like a set of CV shafts would, but as far as function goes, they work perfectly well. And remember—this isn't a top-dollar car.
PROVEN H-ARM SUSPENSION
The threaded-body aluminum shocks offer a smooth ride thanks to their large 16mm bores—more oil makes for better damping performance. The bellows-style shaft covers seem more durable than thin rubber sleeves that are used by some other buggies.
More classic buggy tech here, with thickly molded H-arms, 3mm aluminum shock towers, and tried-and-true C-hubs with cast steering knuckles pivoting on hingepins and kingpins. The C-hubs have molded-in shrouds to help keep dirt and grit out of the bearings, and the hingepins are nutted so there are no e-clips to vanish. The star of the suspension show is the shocks, which are machined aluminum and feature large 16mm bores with threaded bodies for easy preload adjustment. The shocks are left natural and add a bit of brightwork to the otherwise black-on-black buggy.
NITRO-SPEC 3.25MM ALUMINUM CHASSIS
THE 835E'S CHASSIS COMES STRAIGHT FROM THE STANDARD NITRO BUGGY PLAYBOOK, AND SIMPLY ADDS A BATTERY TRAY AND A MOTOR MOUNT TO MAKE THE CONVERSION TO ELECTRIC POWER. AS SUCH, YOU GET A VERY STOUT PLATFORM.
The 835E is, at its core, a nitro buggy with its engine, fuel tank, and throttle servo replaced by a speed control, motor, and battery. Not a bad way to make a tough electric buggy!
The 835E's chassis comes straight from the standard nitro buggy playbook, and simply adds a battery tray and a motor mount to make the conversion to electric power. As such, you get a very stout platform. The chassis plate is a thick aluminum slab that has been stamped to include up-angled sides to increase its stiffness. Plastic buttresses reach down from the front and rear gearboxes to lend additional rigidity, and it's a very solid combo overall. The machined aluminum motor plate is robust at 5mm thick, and the ample battery tray can hold a variety of packs beneath its three hook-and-loop straps. Plastic side-guards bolt to the chassis and close the gap between the body and chassis to help keep dirt out of the works, and the receiver box is gasket-sealed to keep water out. Overall build quality is very good, with attractive finishes and no rough edges (both literally and metaphorically).
The 835E's T240FS 2.4GHz system is dependable and basic, offering the usual trim dials and the welcomed feature of dual-rate steering (the controls are tucked beneath a flip-up cover on the top of the transmitter). The wheel is slightly offset and dropped for middle-of-the-road ergonomics that should feel comfy to any driver, and the foam grip offers a much nicer feel than a solid-plastic wheel (as some low-buck radios use). Range is good and control precise. The only ding I can give the T240FS is in regard to its bind button, which is recessed and requires a tool to depress it—even though it's hidden beneath a cover.
What is “Dual Rate”?
If you're reading RC Car Action, then surely you understand that turning the transmitter's wheel left and right makes the steering servo turn the car's wheels left and right. And the farther you turn the wheel, the more sharply the car turns. By adjusting the transmitter's “dual rate” setting, you can adjust the maximum amount of steering angle the car has. But dual rate does not merely adjust where the steering servo's stops (or “endpoints”) are; it also changes the steering rate (hence the term). Let's say the steering wheel turns 60 degrees, and this makes the servo give the car's front wheels a steering angle of 60 degrees. That's a rate of 1:1. But, if you “turn down” the dual rate so that the front wheels' steering angle is 30 degrees when the steering wheel is at its full 60-degree position, the rate is now 2:1. Why do this? If traction is low, less steering makes a car easier to drive—instead of making smaller inputs to maintain control, you just use dual rate to alter how much the car reacts to your inputs.
BEHIND THE WHEEL
FOR BLASTING AROUND YOUR LOCAL PARK, THE 835E IS A CHAMP. IT STEERS WELL AND HAS THE HOLDING POWER TO KEEP ITSELF POINTED IN THE RIGHT DIRECTION …
The 835e is a value-packed buggy with not only a lot of features included, but also a great amount of expandability for when the time comes and you want to bring it to the next level. To test the 835, I first installed a TrakPower 2S LiPo and headed to a local baseball field. Over the gravel driveway and baseline dirt, the buggy is very well mannered and easy to drive. Running on 2S power as many newcomers might, the car has enough speed to have fun but not so much yank that it gets out of hand easily. On-power, the steering has a moderate amount of understeer as the buggy squats on the rear tires. However, getting things turned around is as simple as lifting partially off the trigger. With the weight transferring forward, the rear end rotates in a controlled slide that the 4WD is able to keep up with and keep things in line. Jumping the 835e is very tame. For a buggy of its 1/4 weight and size, I have to say that it jumps very nicely. Level controlled flight is done with the same ease as mid-air corrections thanks to its powerful brushless system. Landing is a little on the soft side thanks to its lighter weight shock fluid and piston settings but nothing too drastic, just a light slap on the ground off higher jumps and the buggy is back on its way. For blasting around your local park, the 835e is a champ. It steers well and has the holding power to keep itself pointed in the right direction while the medium compound tires have enough tread and density to last a long time, regardless of the surface. Heading to the track, I bumped the power up to a 4S LiPo, which is easily done thanks to the adjustable Velcro battery straps and 4S capable speed control. Driving the 835e around a track with an increase in power exaggerates the understeer/oversteer of the lightly damped car as well as the harder-than-race-ready compound tires. While the buggy's 4WD still did its job maintaining the car's direction, it was a little harder to drive a race line due to the car's harder-than-race spec tires and more park-friendly suspension settings. Luckily, the 835e uses standard size 1/4 wheels and tires so any race tire will fit. Duratrax also makes performance parts such as better shock towers, spring sets and more, so you can upgrade the buggy when you're ready to take on the competition.
Duratrax has cut a few corners to roll the 835E into stores at $400, but I can't fault any of their choices—I'll take the powerful brushless system and high-quality materials and finishes over a fancier radio system and CV shafts any day, especially when the absence of those items has no impact on the fun and durability of the buggy. The 835E is fast on 4S and easy to drive, with all the tuning capability you could ever wish for if you decide to take it to the track. For all-around driving adventure, all I can suggest is twisting the preload collars down the shocks a few turns to raise the car's ride height and increase its ground clearance. Otherwise, this RTR truly is ready to run, and Duratrax has done a good job of combining better-than-expected specs with a high-quality build.
A lot of buggy for $400
Oversized, effective shocks
Taped-in speed control came loose
Need a tool to press the transmitter's bind button