O.S. SPEED B21 Adam Drake Edition 3 is developed in collaboration with O.S. international team driver ADAM DRAKE, who is famous for his deep knowledge and sound technical advice.
By adopting a boost bypass processing for the crankcase, the engine runs more smoothly, and making it even easier to drive. ADAM DRAKE's image color, blue anodized aluminum is applied to the cutting part of the new outer head, and two-color anodized aluminum with new design is used to reduce weight and lower the center of gravity and improve driving performance. You can make a choice of two different carburetor restrictor, 6.5II for buggy and 7.5 mainly for truggy.
Displacement： 3.49cc / 0.213 cu.in.
Bore: 16.4mm / 0.646 in.
Stroke: 16.55mm / 0.652 in.
Output 2.65 ps / 2.61 hp / 34,000 r.p.m.
Practical RPM range: 4,000-42,000 r.p.m.
Engine Weight: 350g / 12.35oz