BSD Racing BS704T (Radio Controlled Model Review)

   Introduced by BSD Racing circa 2009, the BS704T Rock Crawler, is 4 Wheel Drive, 4 Wheel Steer and came RTR, with a 2.4Ghz Radio System, 40A ESC, 540 Brushed Motor, 7.2V Ni-Mh Battery, Charger, 2 x 9KG Waterproof Servos and a choice of three pre-painted bodyshell options (Specifications may vary from country to country).

   This same chassis was also sold by Redcat Racing as the Ground Pounder.

   The 4WD, 4WS model is shaft driven, on a vertical alloy plate, alloy tube link fabricated chassis, with gear type differentials, coil spring over oil filled dampers, telescopic universal joint prop-shafts, dogbone drive-shafts and ball bearings.

   At present, the RC Model Manufacturers, Brands and Distributors covered by us are: ABC Hobby, Academy, Acme Racing, Agama Racing, Amewi, Ansmann Racing, ARRMA, Team Associated, Atomic RC, Axial, AYK, Bolink, BSD Racing, Capricorn, Carisma, Carson, Caster Racing, Cen, Corally, Custom Works, Durango, Duratrax, ECX - Electrix, Exceed RC, FG Modellsport, FS-Racing, FTX, Fujimi, Gmade, GS-Racing, Harm, HBX, Helion, Heng Long, Himoto Racing, Hirobo, Hitari, Hobao, Hong-Nor, Hot Bodies, HPI, HSP, Intech, Integy, Jamara, JQ Products, Kawada, Kyosho, Losi, LRP, Maisto, Mardave, Marui, Maverick, MCD Racing, Megatech, Mugen, New Bright, Nichimo, Nikko, Nkok, Ofna, Pro-Pulse, Protech, PTI, RC4WD, Redcat Racing, RJ-Speed, Robitronic, Schumacher, Seben, Serpent, Smartech, Sportwerks, Step-Up, Tamiya, Team-C Racing, Team Magic, Thunder Tiger, Tomy, Top Racing, Traxxas, Trinity, Tyco, Vaterra RC, Venom, VRX Racing, WLToys, X-Factory, Xmods, Xpress, Xray, XTM, Yankee RC, Yokomo, ZD Racing and Zipzaps.

   This is an ongoing project, with new and "lost in time" RC Models and Brands being added as they are found and although most of those listed above have been covered in relative detail, some are still being researched and will be completed in the near future.

Information and Advice

Electronic Speed Controllers

   ESC were originally developed to be used in conjunction with brushed 27T stock and modified motors in the late 1970s, early 1980s. Compared to modern day Controllers, they were Bulky and heavy, constructed using basic resistors, rheostats, capacitors and transistors, crammed together on a simple circuit board, to provide stepped but smooth acceleration when compared to the old mechanical, servo operated sweeper Speed Controllers. An Electronic Switch to change the direction of current flow was used on some of these early ESC to give reverse operation. Although they were a vast improvement on the old mechanical speedos of the time, they were expensive, jerky to control, and prone to burn out if not carefully looked after.

   As new technology became available, improvements were slowly made, and with the introduction of the new FET (Field Effect Transistors) and some basic mass produced silicon chips, ESC were made smaller and their reliability gradually improved.

   By the mid 1990s, "regenerative breaking" was developed. This meant that energy that would have been lost slowing down the car by effectively turning the motor into a generator, was harvested and put back into the battery. This of course was long before F1 had KERS (Kinetic Energy Recovery System) and adjustable anti lock breaking was introduced.

Sway Bars

   On most forms of RC model cars, Sway Bars, also referred to as Stabilizers, Torsion Bars, or more commonly in some parts as Anti Roll Bars, are often nothing more than a short length of spring steel, clamped to the chassis or sometimes the gearbox of the car, extending out to the lower wishbones direct or connected to the wishbones using short adjustable or fixed length links and ball joints, depending on their position.

   The principal behind the Sway Bar is simple. As the car enters a corner, weight is transferred to the outside wheels, the chassis rolls due to inertia and the suspension dips and grip on the inside wheels is reduced. In an effort to counter this dipping effect and transfer some grip back to the inside wheels to improve traction as you exit the corner, the sway bars transfer the dip of the outside, to pull down the inside wishbones, improving grip on the outside wheels and improving overall stability.

   Sounds complicated I know, but for some tracks sway bars can be a useful tool when you have exhausted all other options to correct your handling problems.

   Tuning your Sway Bars is quite easy.