OS MAX-21XR-B VER. III 3.5cc/.21ci buggy nitro engine

Specs

• Displacement: 3.49 cc
• Bore: 16.27mm
• Stroke: 16.80mm
• Intake ports: 3-port
• Practical RPM range: 4,000 – 40,000 rpm
• Max. power output: 2.42 hp / 34,000 rpm
• Weight: 380Gr

O.S. Engines new 21XR-B Ver.3 3.5cc nitro engine. The sports engine incorporates the DNA of the ultra-successful O.S.Speed line, transplanted into a more budget-friendly package for the average racer. A newly designed crankshaft will improve engine response thanks to a different shape and timing while a more lightweight piston further assists with a crisp engine response on throttle input. The OS Speed-style conrod will offer exceptional durability while a redesigned combustion camber insert optimises power supply especially in the low to medium RPM range while offering stable engine performance at high speeds. Other features include a redesigned cooling head, the engine uses the double adjustment 21 J3-1 carburettor and it comes with 6mm off-road and 7mm GT specific venturi inserts.