Maxima O.S. 21 engine

Maxima introduce their new Maxima O.S. 21 off-road engine, based on the successful O.S. Speed 21ZX-B Spec. II. Carefully modified to achieve even higher performance and improved mileage the engine also features a new blue anodised cooling head with Maxima and O.S. logo.

Specifications:
– Displacement: 3.49cc
– Bore: 16.27mm
– Stroke: 16.8mm
– RPM range: 4,000-42,000
– Power output: 2.65HP
– Weight: 355g

Source: Maxima [maxima-fuel.com]