O.S. have introduced the new R21 3.5cc on-road club racing nitro engine. The R21 is based on the Championship heritage of the R2102 engine and delivers an unbeatable blend of power and value for 1/8 on-road racing. Its crankshaft and piston/liner are designed with premium performance and easy maintenance in mind, which makes it an ideal choice for beginners. This engine is upgradeable with high-performance O.S. Speed parts, letting you realize your full winning potential.
- The perfect power plant for rookies and club racers.
- Newly developed crankshaft and piston/liner with the capability to upgrade later to a Spec-class performer.
- RP7 Turbo glow plug.
- 8.5 mm carb reducer.
- Speed flywheel collet.
- Exhaust seal ring.
- Dust cap set.
- Displacement: 0.213 cu in (3.49 cc)
- Bore: 0.633 in (16.08 mm)
- Stroke: 0.677 in (17.20 mm)
- Practical RPM: 4,000-44,000
- Power Output: 2.71 hp @ 32,000 rpm
- Weight: 12.35 oz (350 g)
- Includes: RP7 Turbo glow plug, exhaust seal ring, 8.5 mm carb reducer, dust cap set