Ultimate MXZ engine + Airmax filter

This is the .21 Motor with 3 long stroke transfers Ultimate MXZ with Ultimate Airmax Air Filter. This engine is manufactured by the prestigious Japanese brand O.S. Engines following these characteristics:

Head

The MXZ features the same head as its predecessors with a new laser design. This 8-fin head has a very low center of gravity and is designed to direct most of the airflow it receives directly to the spark plug. By cooling the spark plug, we achieve more stable carburetion and idle.

Carburetor

Once again, for the MXZ, the star carburetor from O.S, the 21 J3 model, has been chosen. Unlike the original OS carburetor, the high needle holder has been redesigned with fins similar to those of the head. This design significantly cools the fuel inlet to the carburetor. Thanks to this innovative design, the temperature of the carburetor is cooler and more consistent, resulting in greater idle stability, increased engine power, and reduced fuel consumption.

Another important modification is the carburetor barrel puller, which now has two screws instead of one. The new design of this piece allows for angle adjustment in any position without the need to disassemble the engine. This carburetor enables more precise carburetion adjustments, a very interesting detail for more experienced pilots.

Crankshaft

The MXZ crankshaft is 14mm and features a lubrication hole and paste to improve flow.

Bearings

The MXZ comes equipped with the original O.S steel rear bearing and a steel front bearing with a double cover from Ultimate racing.

Venturi

The engine incorporates the new 6.5mm FlowMax Venturi. With an innovative design that is longer than standard O.S. venturis and wider at the base, unlike all others, it ensures that the bottom of the venturi and the carburetor have exactly the same diameter. This new geometry improves fluid dynamics, providing extra power that allows the use of smaller venturis without decreasing power, and consequently enhances the engine's range.

Liner and Piston

The liner features 3 intake transfers and one exhaust to ensure minimal fuel consumption, as well as smooth and linear power. Both the liner and the piston are made from high-quality aluminum bar to ensure maximum durability of our engine equipment.

Technical Specifications

Displacement: 3.49 cc

Bore x Stroke: 16.27x16.80mm

Liner: 3 + 1 ports

Practical RPM range: 4,000 ? 40,500 rpm

R.P.M. (power): 2.55 hp / 34,000 rpm

Weight: 350 gr

Crankshaft: 14 mm

Carburetor: 21 J3

Spark Plug: P3

Exhaust Position: rear