Max R21 1/8 radio -controlled heat engine

RC 1/8 Engine O.S. MAX-R21

Developed for leisure RC use, the O.S. MAX-R21 offers an excellent balance between performance, reliability and ease of use. It is perfectly suited for beginners as well as drivers looking to efficiently replace a stock engine on their 1/8 scale on-road RC car. Its robust and proven design ensures smooth, consistent operation, even during extended running sessions.

What does MAX-R21 1/8 mean?

The designation MAX-R21 carries a precise meaning. At O.S. Engines, MAX refers to a range of high-performance nitro engines derived from racing technology. The letter R stands for Racing, adapted here for leisure use, while 21 refers to the displacement in cubic inches (0.21 cu in), the standard size for 1/8 scale nitro RC engines. This guarantees full compatibility with most 1/8 on-road RC chassis.

A leisure engine built on racing know-how

Although designed for leisure, the O.S. MAX-R21 1/8 engine fully reflects the brand’s racing DNA. O.S. Engines has won numerous international titles, and this experience is evident in the machining quality, precise tolerances and stable performance.

The result is an engine that is easy to tune, with forgiving carburetion, making it ideal for learning or returning to RC driving. Its smooth power delivery, balanced torque and consistent behavior allow drivers to focus on driving rather than constant adjustments.

Ideal for beginners or as a replacement engine

The O.S. MAX-R21 engine for 1/8 scale RC cars is ideal for:

• getting started in 1/8 scale on-road RC leisure driving,

• replacing a worn or underperforming engine,

• improving reliability for regular use,

• enjoying O.S. quality without entering full competition racing.

Reliable, efficient and accessible, this engine is an excellent choice for fully enjoying 1/8 scale nitro RC cars, backed by a world-class manufacturer.