HOT BODIES D812

Jul 01, 2013 No Comments by

WORDS ERICH REICHERT@ERICHRCCA PHOTOS HOPE MCCALL

⅛ SCALE NITRO 4WD BUGGY | UNASSEMBLED KIT

This buggy puts a factory team ride in the hands of the club racer to make it a true people's champion


The Hot Bodies D812 is the product of countless races and years of development by HB's engineers and team drivers. At the 2012 ROAR Nationals in Lost Creek, PA, the team kept their latest creation out of the public eye as best they could but after taking the win, they had to fight off the media who were eager to show the world what sort of new top-secret designs there were behind the new national champion and Worlds hopeful. From first glimpse, the car was out of this world and bursting at the seams with wild, new designs and different takes on how the everyday ⅛ buggy should be. The buggy that graces these pages is the finished product of those races, hours and hours of testing, and outspoken performance on both the national and world levels of competition. Packed full of the designs that stunned us just one year ago, the D812 is so much more than just HB's newest offering. To you, Joe Weekend Warrior, it's your sponsorship packet, your first shipment of gear, and your signed contract to join the team.

PACKED FULL OF THE DESIGNS THAT STUNNED US JUST ONE YEAR AGO, THE D812 IS SO MUCH MORE THAN JUST HB'S NEWEST OFFERING.

Monocoque Suspension

All-new monocoque suspension arms are found on all four corners and feature bolt-on covers that increase strength and stiffness while keeping dirt out. Attached to each corner, the arms are held to the ground by a set of aluminum-bodied, 16mm long-travel shocks that are mated to 5mm aluminum shock towers. A closer look at the inner arm mounts reveals the level of tuning that HB offers both their team drivers and their customers. The D812 includes a full set of blocks that allow you to set both toe and rake however you wish to dial it in. The overall suspension system features aluminum hubs and steel turnbuckles to keep it efficient and lightweight.


VEHICLE SPECS

  • Item no. : 109428

  • Scale: 1/8

  • Price: $520

  • Weight, as tested: 122 oz., 3,400g

  • Chassis: 3mm aluminum plate

  • SUSPENSION

  • Type: Lower A-arm with adjustable upper camber link

  • Inboard camber link positions (F/R): 4/4

  • Outboard camber-link positions (F/R): 3/4

  • Shock positions, towers (F/R): 6/5

  • Shock positions, arms (F/R): 2/2

  • Shocks: Threaded 16mm aluminum body shocks with bladders

  • DRIVETRAIN

  • Type/ratio: Shaft drive with 4.4:1

  • Spur gear/pinion: 48T/16T

  • Slipper clutch: None

  • Differential: Bevel gear, fluid filled

  • Driveshafts: Aluminum constant velocity style

  • Bearings: Metal-shielded

  • WHEELS & TIRES

  • Wheels: White dish style, 17mm hex

  • Tires: Not included

  • Inserts: Not included

  • ENGINE AND ACCESSORIES

  • Engine: HB 21XZ-B Hara Edition

  • Displacement: 3.49cc/.213ci

  • Carburetor: Slide valve

  • Pipe/header: O.S. T-2060SC

  • Fuel Capacity: 125cc

The chassis on the D812 moves everything as close to the centerline as possible for optimum balance and handling. Out back you'll notice the replaceable skidplate allows you to freshen up the chassis when things take a beating.

ALL-NEW MONOCOQUE SUSPENSION ARMS ARE FOUND ON ALL FOUR CORNERS AND FEATURE BOLT-ON COVERS THAT INCREASE STRENGTH AND STIFFNESS WHILE KEEPING DIRT OUT.

Low Rotating Mass Drivetrain

Plastic covers are bolted to the monocoque suspension arms to increase their stiffness and keep dirt out.

Hot Bodies aimed to increase acceleration by lightening the entire drivetrain. Lightweight steel gears were used throughout the buggy and small diameter diff and pinion gears were selected (44/10) to keep the amount of mass down. Mated to the clutch bell, the center diff lines up the drivetrain straight down the middle of the chassis and transmits power to the front and rear through a pair of shafts. On both ends of the buggy, another fluid-filled, 4-gear diff spools the power out to the wheels and to the ground through a set of CV-style aluminum axles with captured boots that keep dirt out. The drive system as a whole is very free and spins easily, even by hand, due to its low rotating mass.

Lightweight Chassis

The engine and fuel tank are just to the left of the center of the car. On the opposite side, the one-piece radio tray off sets them to balance the chassis laterally.

The D812 features a narrow, lightweight 3mm aluminum chassis that positions all of the buggy's components as low and close to the centerline of the car as possible for optimal handling. The top of the chassis has been milled out to further reduce its overall weight while the bottom rear section is also milled and fitted with a replaceable steel skidplate to extend chassis life. An overall view of the buggy's layout shows its most important design in action; the engine, fuel tank, and radio tray hug the center-line of the car and are off set just enough to balance things, such as the main body of the engine, that otherwise could not be directly on center.

Team Driver Powerplant

The Hot Bodies 21XZ-B is the product version of the engine that Atsushi Hara ran in the 2008 and 2010 IFMAR Worlds. Every spec was replicated down to the finest detail to bring you the same engine Hara runs.

The engine, pipe, and fuel are not included with the D812, so for the test, our buggy was fitted with a Hot Bodies 21 XZ-B Hara Edition .21 engine and O.S. T-2060SC pipe. This is the same configuration that Hot Bodies team driver and former World Champion Atsushi Hara used to power his way to an IFMAR Worlds podium finish in Thailand in 2010. The O.S.-based engine is replicated to the exact specs that Atsushi ran at the 2010 Worlds and comes complete with a P3 glow plug. We ran O'Donnell Speed Blend 30% fuel to finish out the buggy in team spec trim.

What is a Fluid-Filled Diff?

This morning, you may have put syrup on your pancakes and while you didn't notice, they were teaching you a lesson about your 1/8 buggy. Sometimes, the syrup takes a long time to pour out while other times it's much thinner and a hefty pour results in syrup that gushes out all over the place, soaking your delicious breakfast. Fluid-filled differentials rely on silicone fluid of various thicknesses to adjust the speed of their operation and much like your syrup, the thinner fluid allows things to move much faster. Inside the diff, gears spin around through the fluid to actuate the diff mechanism. Without the fluid, things would spin very easily and the diff would constantly be changing which side it transfers power to. By using thicker fluid, the diff moves slower and holds power to both wheels until the forces on it overcome the slower movement and send the rotation of the drivetrain out through one side.

BEHIND THE SCENES THE D812


ON BOTH THE NATIONAL AND WORLD LEVELS, THE D812 HAS BEEN A LANDSLIDE SUCCESS IN A SHORT TIME. WHILE ITS DEVELOPMENT HAS BEEN A LONG JOURNEY, ITS SUCCESS HAS BEEN SWEET. WE SAT DOWN WITH HOT BODIES FACTORY TEAM DRIVER AND 2012 ROAR NATIONAL CHAMPION TY TESSMANN TO GET THE INSIDE SCOOP ON HOW THE HOTTEST NEW 1/8 BUGGY CAME TO BE:

The Hot Bodies D8 was always a good car for us. Four D8 cars made the A-main in the 2008 IFMAR Worlds and Atsushi Hara won, but it lacked rough track handling and the ability to make substantial setup changes. In 2011, my dad and I decided that we needed to make some changes to the buggy. We felt like we were falling behind everyone else, so using slow motion video cameras and a rough layout on my home track, we did a lot of work to find out why the D8 didn't handle blown-out tracks very well. With what we learned, we headed to California to test the first changes we had made to the car at the 2011 Gas Champs. I ended up TQ'ing and winning the race with the changes we made. This was the first higher profile race I had ever won with the buggy, and my confidence in the class increased.


FOR US, WINNING AS A TEAM COULDN'T HAVE BEEN A SWEETER RESULT WITH THE BRAND-NEW CAR. THE CAR I RAN AT THE NATIONALS IS THE EXACT SAME CAR THAT IS AVAILABLE NOW AS THE D812

This got the attention of the HB R&D team and Torrance Deguzman, Hot Bodies' newest designer/engineer, was assigned to the project and worked very closely with me, Atsushi Hara, Muira Masayuki, and my dad to improve the D8. Unlike cars designed by other companies in the past, this car was designed on the track rather than on a computer. Parts were hand Dremeled, modified, prototyped, and tested on the track before ever coming to the final production. We were told to keep everything under strict confidence and I realize that this was very frustrating for a lot of people, but sometimes promising something new for months on end and never coming out with it is worse.

The next few months saw a massive amount of testing; some things worked and some didn't. I spent a lot of time in California testing leading up to the 2012 Nitro Challenge where I TQ'd and won. Although the parts on the buggy were from other HB cars, modified, Dremeled, a few prototype parts, and the odd part or two from other cars, this was the race that decided the car was ready for production. We went to Silver State that year and Torrance had put together the first pre-production D812, but he insisted that we bring the Nitro Challenge car with us just in case. Although we had no time on the new car, we put a setup on it that was similar to what we had been running on the “Franken-buggy,” as it had been called on the Internet, and we tweaked the car during practice and qualifying. It was nice to have a car that we could finally make actual adjustments to the geometry of. We struggled a bit in qualifying; I managed to qualify fifth, so Saturday night right after qualifying we headed to Silver Bowl RC Park in town with Torrance to try and figure out the setup. No one knew at the time that we were even running the car, and we kept it completely hidden. Although I didn't win, I think we did pretty well. The car felt awesome and I led the race for more laps than any other driver, but unfortunately, with two flame-outs, I was only able to finish fourth.

After that, we took the car home with spare parts and until the ROAR Nationals, my dad and I were at the track just about every day. We knew the car was good, but we wanted to be more familiar with it so we would know exactly what each setup change would do on the track. We went back and forth so many times that we wore out everything that we had brought home with us. When we got to Nationals, we were a little lost at first. The track was awesome but different than anything that we had run on before. Practice and qualifying went alright, but because of what we had learned at home and having Torrance there to help us out, we were able to find a setup for the car. For us, winning as a team couldn't have been a sweeter result with the brand-new car. The car I ran at the Nationals is the exact same car that is available now as the D812.

Winning the Nationals with the D812 was the high-point of my career, but I have to say that this accomplishment is not just mine. I have to thank everyone at Hot Bodies for their hard work, Tatsuro Watanabe, the owner of Hot Bodies, for believing in me, my dad, and especially Torrance Deguzman for working so hard with us, believing in us, and helping to create such an awesome car.

If you want to dial in your D812 like the pros, check out Ty's setups on tytessmann.com.

BEHIND THE WHEEL

WHEN THINGS WORK WELL, GOING FAST IS EASY AND AT THE HANDS OF A MORE EXPERIENCED DRIVER, THE D812 IS A DEADLY WEAPON.


WELL-BALANCED PLATFORM

At the heart of the D812's track manners is its chassis balance. Having everything mounted low and close to the center allows the buggy to keep the wheels on the ground longer, which translates to massive amounts of grip. While it makes things tight to work with inside the buggy, on the track, the weight distribution's advantage is massive. The buggy displays very little chassis roll and is very quick on its feet, transferring weight from side to side and allowing the buggy to steer hard without losing its cool. In the air, the buggy is nothing shy of jumping level and landing without incident.

DYNAMIC DAMPING

The most obvious addition to the D812 is its massive 16mm shocks. These shocks are not only oversized compared to their predecessors on the D8 buggy, they're also designed to articulate the 812's long travel suspension arms and keep the tires stuck to the dirt. Over large jumps, the suspension drops down awaiting its return to Earth with no more than a mere plunge and a light tap of the ground before getting the buggy off and away again. High-speed corners are controlled and level-headed as the inside arms stretch down to keep the D812 shiny side up. Through rough sections, the stock settings from the manual work well at soaking up bumps and keeping the buggy under control and pointing forward.


Innovative, race-focused design

Clunk-style fuel tank

As close to a factory ride as most will get


Room to work on things is at a premium

One-piece radio tray is nice but tough to run wires

A lot of disassembly required to remove diffs

WARP FACTOR 5, MR. HARA

Topping off the 125cc fuel tank is the beginning of something very special. From first pull of the trigger, the HB 21XZ-B Hara Edition is a powerhouse of an engine with dirt-tearing torque coupled with F1 pitched screams and blistering top speed. The engine is matched very well to the T-2060SC pipe and gets on it quickly, allowing for a very linear feel to the throttle. The Goliath-sized acceleration is also due in large part to the D812's lightweight drivetrain, which keeps things spooled up with ease. Overzealous driving may land the buggy on its lid but not to worry, the tanks clunk-style design allows the pickup to slide down and continue to pick up fuel while you scream for a corner marshal. On about a half a tank and modest carb settings, the D812 is able to stay upside down for a full tank for well over 30 seconds without shutting off.


TEST GEAR

  • Futaba 4PKS-R Radio System

  • Item no. FUTK4903

  • Price: $550

  • Futaba BLS157HV Brushless Servo

  • Item no. BLS157HV

  • Price: $190

  • Hot Bodies 21XZ-B Hara

  • Edition Engine

  • Item no. 106540

  • Price: $300

  • O.S. T-2060SC Tuned Pipe

  • Item no. OSM72106135

  • Price: $170

  • MaxAmps 1290mAh LIPO rx pack

  • Item no. N/A

  • Price: $35

  • O'Donnell Speed Blend 30% (gallon)

  • Item no. ODOP4431

  • Price: $120

  • Pro-Line Racing V2 Pre-Mounted Blockade M3 Tires

  • Item no. PRO9039-32,

  • Price: $31/pair

Final Word

You may not claim to be the hotshot at your local track or know all there is to know about setup, but with the D812 buggy you make the leap from zero to hero in a matter of minutes. Its superior balance and poise make it both easy and quick to drive and it can take even the most intermediate driver and put him on a higher level of driving. When things work well, going fast is easy and at the hands of a more experienced driver, the D812 is a deadly weapon. Its ability to accelerate at will, grab traction, and hold any cornering forces you can throw at it make it easy to see how it has shared such great success over the past year.

SOURCES

Performance Tests

About the author

Associate Editor I can say that I’ve never done ANYTHING as long as I’ve been into RC. I got my first car when I was 11 and never looked back. Since then I’ve owned hundreds of cars and trucks and raced everything from Off-Road to Boats but I’m an Oval racer at heart. Whether I’m down siding a jump or going fast and turning left, it’s all on and my foot is to the floor! I love seeing new people discover our hobby and helping anyone I can enjoy it more. When I’m not racing or writing, I like to restore vintage RC cars and organize the Vintage Offroad Nationals. I’m also a dad and enjoy teaching my son how to drive and watching him get into this hobby on his own.
No Responses to “HOT BODIES D812”
Copyright © 2014 Air Age Media. All rights reserved.