GB-02
The GB-02 chassis is an evolution of the GB-01 chassis; the GB-01 and GB-02 chassis differ in the front suspension: in the GB-01 model it is a lower triangular arm configuration with upper tie rod (on the left in the image below) and in the GB-02 model it is a double wishbone suspension (on the right in the image below). The GB-02 chassis solution is more robust, allowing improved performance during jumps and providing more space for adjusting the camber of the front wheels compared to the solution adopted on the GB-01 chassis. Therefore, the GB-02 chassis is the natural technical evolution of the GB-01 chassis.
There is a set of parts that allows the conversion of a GB-01 chassis into a GB-02 chassis: set number 40551 defined as the “GB-02 Front Conversion Set.” This set mainly consists of the following parts (with their codes shown in the image below): central suspension frame (A), right suspension tower (B), left suspension tower (C), suspension arm (4 pieces D, E, F and G), support for the two towers (H), front bumper (I), right wheel hub (L), left wheel hub (M), headlight (2 pieces O and P), stainless steel shaft 3x38mm (4 pieces), 7mm ball connector (4 pieces), 2mm spring ring (9 pieces), 850zz ball bearing (4 pieces), 2.6mm nylon nut (2 pieces), 2.6x20mm screw (2 pieces), 2.6mm washer (2 pieces), 2.6x4mm ball connector (6 pieces), 2.6x8mm screw (16 pieces) and 2.6x12mm screw (4 pieces).
The following factory pre-assembled models belong to the GB-02 Tamtech Gear family by Tamiya and come complete with electronics, battery and charger (the charger is mainly included for the U.S. market and a few other markets worldwide):
- Buggy Champ Mini, model number 56707, released in 2007 and available on the market until 2008; 1/14 scale model.
- Blue Champ Mini, model number 84105, released in 2009 and available only in the Japanese market until 2010; 1/14 scale model.
Technically, the GB-02 chassis has the following features:
– the only difference from the GB-01 chassis lies in the front suspension, the two shock absorber towers, the front bumper and the front subframe. The shock absorbers are the same for both the GB-01 and GB-02 chassis.
All other technical features are shared with the GB-01 chassis:
– Rear-wheel drive powered by a type 370 motor with a Teflon pinion gear (refer to the four factory-supplied pinions with 12, 14, 16 and 18 teeth highlighted in the image below, first row on the left). Technical specifications of the RK370 motor at maximum efficiency: 10,600 RPM, torque 5.4 Nm and current draw 1.8 Amps. To improve performance, install accessory number 40537 described as “Tamtech-Gear Sports Tuned Motor SPT”
– Factory pre-assembled ball differential (code 40106 highlighted in the image below, first row on the right); Tamiya chose to supply the differential already assembled due to its compact size. With the release of the GB-01S chassis, Tamiya introduced a more durable planetary gear differential. This new differential is compatible with the GT-01 and GB-01x chassis (code SP-1685 or 51695 described as Tamtech Gear GB-01S Spare Gear, highlighted in the second row of the image below)
– The transmission is equipped with an anti-slip clutch. The anti-slip clutch mainly consists of two discs held together by a spring loaded with a bolt. The clutch performs two functions to compensate for the lack of grip between the ground and the wheels.
The first function is to preserve the mechanics during jumps. When jumping, the model is airborne and the drive wheels rotate freely without ground resistance: the wheels tend to increase their rotational speed. During long jumps, the motor’s rotational speed is modulated by the operator to keep the model stable by adjusting the landing angle. In both cases, when the model touches the ground, the wheel speed must align with the actual speed of the model, abruptly changing the rotational speed. This puts stress on the transmission gears.
The second function is to protect the gears from premature wear when the motor, during a sudden acceleration, increases its rotational speed faster than the wheels can respond. The same occurs during sudden deceleration. The clutch prevents the model from losing grip and avoids unnecessary strain on the gears.
This dual role of the clutch ultimately preserves the mechanics within the gearbox, where the motor pinion is the gear most exposed to stress.
To achieve optimal performance, the clutch slippage must be adjusted by acting on the calibration nut (indicated as “BA9” and highlighted in red in the image above on the left). Follow the instructions by compressing the spring until reaching a total length of 4.2 mm to establish an initial working point for the anti-slip clutch. Place the model on a table or a flat surface, switch on the electronics, hold the rear wheels firmly with your hands and briefly accelerate.
Two outcomes are possible: the model tends to move and the front end with the front wheels lifts off the surface (following the red line shown in the image below), or a sound is heard from the gearbox indicating that the clutch is engaged and the front of the model remains on the surface. In the image, you can see the hand holding the rear wheels and the expected movement of the front axle in response to the burst of acceleration (highlighted by the red arrow).
The optimal configuration occurs when the front end and front wheels lift slightly, losing contact with the surface; this serves only as a starting point. The best setup depends on the track surface conditions and its grip level; calibration is necessary based on this factor.
The two worst configurations represent the extremes of adjustment: an overly compressed spring or an overly loose spring. In the first case, the gears are directly and firmly connected to the wheel axle, causing the clutch to lose its function completely. In the second case, the spring is so loose that it fails to transmit any movement to the wheels, making it impossible for the model to move. In the Tamiya world, the first anti-slip clutch called TTC (which stands for Tamiya Torque Control) was engineered for the Super Astute model, released in 1991.
– Driveshaft with complete ball bearings to reduce wear and increase system efficiency, thereby extending operating time
– Central bathtub chassis designed to ensure low overall weight and lower the model’s center of gravity. The battery compartment is integrated into the chassis, accessible from underneath (see the image below with batteries highlighted in red). The GB-02 family’s bathtub chassis differs from that of the GT-01 chassis, but it is the same as the GB-01.
– Four independent suspensions with four spring-loaded mini shock absorbers, which are long and thin and perfectly replicate those used in 1/10 scale models. Two alternatives are available to improve performance by replacing the factory-installed spring shock absorbers: set number 40529 described as “TamTech-Gear CVA Damper Set (4 Pcs.)” or the most high-performance option, set number 40513 described as “GB-01 Aeration Oil Filled Damper (4 pcs).”
– Most screws in models equipped with the Tamtech Gear GB-02 chassis have M2.6 threading.
– The remote control system is based on 27MHz AM technology and consists of the Expec SP TTU-03 transmitter (code 17254324 or 7254324) and the TRU-02 receiver (code 45036). The onboard electronics include the TSU-02 servo and the TEU-102 BK ESC (image below taken from the packaging). As of today (2025), these are no longer available on the market. Note that the TEU-102 BK does not have a “cut-off” function, so it cannot be used with LiPo batteries. LiPo batteries must not be fully discharged and without the “cut-off” function, it is advisable to replace the electronic speed controller if you want to use the latest generation batteries.
Here is a list of all the parts that serve as accessories to improve performance or were not included in the factory package of the GB-01T chassis; some accessories are shared with the GT-01 family and other GB-01xx families:
40501 setting spring set
40502 GB-01 Aluminum Pinion Gear (12T)
40503 GB-01 Aluminum Pinion Gear (14T)
40504 GB-01 Aluminum Pinion Gear (16T)
40505 GB-01 Aluminum Pinion Gear (18T)
40506 GB-01 Rc Reinforced Sus Shaft
40507 GB Wheel Bolt/Collar Set (Pink colour)
40508 GB 2.6 x 29 mm Aluminium turnbuckle shaft (6 pcs Pink colour)
40509 GB-01 Aluminum Diff Cup
40510 GB-01 Aluminum Motor Plate (Pink colour)
40511 GB-01 Aluminum Wheel Hub (Pink colour)
40512 GB-01 Aluminum 4mm Ball Connectors (Pink colour)
40513 GB-01 Aeration Oil Filled Damper (4 pcs)
40514 GB-01 Sport Tuned Motor equivalent to RK-370-SD-3265; technical specifications at maximum efficiency: 15,000 RPM, torque 6.8 Nm and current draw 2.1 Amps. In addition to the code, it can be recognized by the black rear shield. Also available as 54919 “Torque Tuned motor.”
40515 GB-01 Bumper Set (the side bumpers can be installed on the BG-02 chassis)
40516 GB-01 Aeration Oil Damper Maintenance Kit
40518 GB-01 Carbon Damper Stay rear
40519 TamTech-Gear Setting Spring Set (Short)
40520 GB-01 Aluminum King Pins (Pink colour)
40522 GB-01 Aluminum King Pins (Blue colour)
40523 GB Wheel Bolt/Collar Set (Blue colour)
40524 2.6 x 29 mm Aluminium turnbuckle shaft (6 pcs Blue colour)
40525 GB-01 Aluminum 4mm Ball Connectors (Blue colour)
40526 GB-01 Aluminun Wheel Hub (Blue colour)
40528 GB-01 Aluminum Motor Plate (Blue colour)
40529 TamTech-Gear CVA Damper Set (4 Pcs.)
40530 TamTech-Gear Low Friction O-Ring Set for Oil-Filled Dampers
40537 Tamtech-Gear Sports Tuned Motor SPT equivalent to RK-370-SD-4045; technical specifications at maximum efficiency: 21,000 RPM, torque 7.7 Nm and current draw 3.3 Amps. In addition to the code, it can be recognized by the red rear shield. Among the motors in the catalog, it offers the best performance. Also available as 54860 “Sport Tuned motor.”
40538 Aeration damper attachment bolt (4 pcs)
40539 Aeration oilfilled dampershort case (2 pcs)
40540 4 x 3 mm Aluminium step ball connector (4 pcs Blue colour)
40541 4 x 10 mm Aluminium ball connector (2 pcs Blue colour)
50548 GB-01 GB-01T GB-02 GT-01 Aluminum Front Upper Plate (Blue colour)
40549 GB-01 Titanium screw set
40551 GB-02 Front Conversion Set
