Spotlight: Speed Tuned B2101 by O.S.

In 2014 Ty Tessmann powered to first at the IFMAR Worlds running the Speed Tuned B2101, paired with a T-2090SC Tuned Pipe. The engine delivered for Ty — and its advantages can now belong to any off-road racer.
Those advantages include faster acceleration, off the starting line and out of corners. A low center of gravity adds stability and predictable handling. Throttle response is so immediate, the power seems to flow right from the driver’s fingers. The factory-tuned, fiercely reliable B2101 is ready to keep the successes coming. Look for the B2101 now, with distinctive laser-etched Speed Tuned graphics on the cylinder head.
• Lowered machined cylinder head with maximized cooling
• DLC crankshaft with balanced tungsten weights and optimal intake timing
• Efficient, reliable Type 21J carburetor
OSMG2045
Displacement: 0.211 cu in (3.46 cc)
Bore: 0.646 in (16.4 mm)
Stroke: 0.646 in (16.40 mm)
Practical RPM: 4,000-42,000
Output: 2.61 hp @ 34,000 rpm
Weight: 12.42 oz (352 g)
Includes: 21J carburetor; 6 mm and 6.5 mm carb reducers; P3 Turbo glow plug; dust cap set (3 mm, 16 mm and 18 mm); exhaust seal ring
Requires: Glow fuel, T-2090SC Tuned Silencer Set
Learn more about the O.S. Speed Tuned B2101 engine by visiting its product page at
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