42384 TRF421 CHASSIS KIT Official photos and detailed information.

Tamiya.com has now uploaded the official photos and info for the exciting new Tamiya TRF421. Obviously I am pretty excited about this new car, taking design cues from many of the top tier chassis and adding a bit of Tamiya magic into the mix.. 

Here is the translated info. 

The 2-belt drive 4WD touring chassis, which bears the name of Tamiya RC's highest peak "TRF", is now fully remodeled for the first time in two years. The new shape of the carbon lower and upper deck moves the motor position 22.7mm forward compared to the previous model "TRF420X". The center shaft is placed in the center of the chassis, and the drive belt is of equal length front and rear. The front and rear pulleys also have a new shape. This change reduces pitching during throttle operation and achieves a stable drive. The shape of the front and rear bulkheads has been changed in pursuit of a lower center of gravity, and a new USBB (ultra short big bore) damper is mounted with aluminum stays. Fine angle adjustment is now possible using spacers. The suspension uses highly rigid A-arms on the top and bottom. The lower arms are the same in the front and rear, and the longer span allows the roll attitude to change more linearly during cornering, improving stability during control. Please look forward to the performance of the TRF421 chassis, which aims for even greater heights through drivetrain optimization, chassis flex, and a low center of gravity.

The centre shaft is placed in the middle of the chassis, and the drive belt is of equal length front and rear. The front and rear pulleys also have a new shape. This change reduces pitching during throttle operation and achieves greater stability.


The shape of the front and rear bulkheads has been changed in pursuit of a lower centre of gravity, and a new USBB (ultra short big bore) damper is mounted with aluminium stays.


The damper has been completely redesigned. The USBB damper is 5.5mm shorter than the SSBB damper, resulting in a lower centre of gravity and reduced weight. Dramatically improving handling response.

Two types of shock ends are available, one for the front and one for the rear, and by adding a 0.5mm difference between the front and rear, it is possible to adjust the piston height to the same level according to the vehicle height.

By moving the motor position 22.7mm forward compared to the TRF420X, the centre shaft is placed in the middle of the chassis. Equal length front and rear 116 tooth belts reduce pitching moment when operating the throttle, achieving a very stable drive. The spur gear can be fixed with a single dedicated nut, greatly improving work efficiency when installing and removing it.

The stabilizers have had an overhaul. The new high-precision stabilizer features a common design for the front and rear has been adopted by reviewing the material and hardening part. By lowering the mounting position below the drive shaft, the centre of gravity is lowered and ease of maintenance is improved. The kit includes 1 x 1.0 mm, 2 x 1.1 mm, and 1 x 1.2 mm, for a wide range of settings. 

The revamped suspension  features a rigid upper A-arm with newly designed geometry. The lower arm has been given a longer span and the installation has been changed from block type to ball type. By placing the lower pivot inside the bulkhead, we have achieved a 7mm longer span while keeping the overall width of the vehicle the same. Set the inner toe angle of the lower arm to 0 degrees, and adjust the toe angle on the upright side.

Two types of upper decks are available: one-piece type and two-piece type, allowing for chassis flex settings. Multiple dedicated mounting screw holes are drilled for fixing to the motor mount, and chassis rigidity can be adjusted in a variety of ways by combining screw mounting.

Cannot wait to get my hands on this new chassis. It will be available towards the end of May.