Kyosho 33155 1/8 USA-1 GP .25 Engine 4WD Off-Road Monster Truck RTR

The original Kyosho Nitro USA-1 set the standard for RC Monster Truck power and performance when it was released in 1990. 30 years later, the torch has passed to the newest Nitro USA-1, which outperforms the original in EVERY respect. Yes, it's that much better… and we even build it for you.
Built on a pickup truck chassis, large diameter tires and big engines with massive horsepower were installed by fun-loving American off-roaders to create the monster truck. These ever-popular monster trucks can be seen on specially-made racing circuits or jumping rows of cars in stadiums across the USA. Many R/C monster truck models have been produced over the years. First among equals is the legendary 1/8 scale USA-1 that embodied the might of American trucking power during the 1980’s and 90’s. Officially licensed by Kyosho in the 1990’s, the R/C model uniquely captured the power and glory of the USA-1. Now it’s ‘comeback-time’ for the USA-1, with modern chassis and drivetrain technology, upgrades unique to the USA-1 throughout, and a newly-designed ‘ULTRA SCALE BODY’ with form and detail finished to display-model standards. The iconic American flag graphic emblazoned on the body makes your heart swell with pride! The chassis features shaft-driven 4WD and 5-link suspension based on the Mad Crusher 2.0 & FO-XX models. Most of the suspension components have been uniquely upgraded and reinforced for the USA-1 at each point to handle the powerful new KE25SP2 engine, and the rigors of monster trucking. A 3-speed automatic transmission produces dynamic acceleration, which is enhanced by a true suspension system to produce "scale" running characteristics worthy of the prestigious USA-1, and make you feel like a monster truck driving god. Released as a pre-assembled Readyset, the USA-1 is almost ready for action straight out of the box.

Pre-assembled chassis with R/C system installed and finished body. Includes pistol-grip Synchro KT-231P+ transmitter.
5-link suspension in combination with shaft-type 4WD delivers exceptional stability over rough roads.
Equipped with KS5031-09MW servos that incorporates durable metal gears.
Ultra-realistic scale body has been recreated under license of USA-1, including the signature color scheme.
Optional LED light set shines bright with LED head & tail lamps and rooftop fog lamps.
Equipped with a new KE25SP2 engine with easy needle setting. Also includes break-in ring to get the engine safely prepared for harder running.
Gleaming polished tuned muffler is equipped as standard.
Front center drive features a telescopic universal shaft to ensure high drive efficiency and prevent shaft dropout issues.
Optional 4WS (four wheel steering) increases turning power. A wide range of other option parts are also available.
8 x AA batteries for transmitter & receiver, fuel, fuel pump and plug heater are required for operation.
Electric version using the same body and chassis components is also available.

Molded and chrome-plated triple carburetors look identical to those used on the real truck, which looks awesome sticking through the hood once the body is attached. Coupled with the growl of the powerful engine, this accessory creates even more original details of the USA-1 more than ever.
Equipped with a new KE25SP2 engine, the easier-to-adjust low-speed needle makes it easier to produce more power than the previous KE25SP engine. The engine is fitted with a pull starter so a starter box isn’t required and engine settings have been optimized at the factory.

The time-tested 3-speed automatic transmission effectively utilizes the full power of the engine. In the low speed range, the torque of the engine is optimized by the ratio of first gear, while the 2nd gear covers the medium speed range where torque tends to be insufficient. Acceleration to maximum speed is achieved smoothly and efficiently.
A 5-link suspension platform controls the rigid front and rear axles to minimize drive loss and deliver superior traction and handling over uneven and varying running surfaces. The large-capacity oil shocks reliably help to absorb the impacts from the running surface.


Combination of big tires with 5-link suspension provides plenty of stroke to overcome large obstacles. Lateral rods that increase suspension rigidity are also standard equipment on front and rear.




Differentials in the front and rear axles are taken directly from a well-developed World Champion 1/8-scale off-road car, and are equipped with metal ring, pinion, and spider gears to handle the power of the 25-class (approx. 4.2cc) engine, all while managing the difference in rotation between the left and right tires during turns for smooth, stable driving characteristics and increased traction.

The USA-1 includes accurate reproductions of the 66-inch agriculture tires and white wheels that were featured on the real USA-1 throughout its career. Foam inserts are installed inside the tires to maximize handling on a variety of surfaces.


The reinforced axle housing thrives under high-power and rough road conditions while improving crash resistance. The scale aspects of the dynamic steering options of the early monster trucks can be enhanced with the addition of optional rear wheel steering to create a true AWS (All-Wheel Steering) system.

Readyset Contents
Pre-assembled chassis with pre-set control linkages
Pre-cut and painted body complete with decals applied
2.4GHz Syncro KT-231P+ transmitter
L shaped hex wrench (1.5mm, 2.0mm, 2.5mm, 3.0mm)
Cross wrench (large)
17mm wheel wrench

Required for Operation
AA-size batteries x 4 for transmitter
AA-size batteries x 4 for receiver
Glow fuel for models
Fuel bottle
Plug heater

Chassis Technical Data
Length                       570mm
Width                         450mm
Height                        281mm
Weight                       4,990g
Wheelbase                360mm
Tread                         F:339mm R:343mm
Tires (F & R)           164×104mm
Gear Ratio                 25.7/19.8/15.6:1
Engine                       KE25SP2 with recoil starter