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Top drivers like Mark Pavidis and Atsushi Hara can vouch for the victory-taking technology of O.S. Speed engines. Both have stood in the IFMAR Off-Road World Championship winner’s circle as a result of its powerful edge. Now another O.S. engine offers you the same advantage with the new O.S. Speed 21XZ-B engine. The O.S. 21XZ-B engine has a completely new design that delivers instant throttle response and impressive torque over the entire rpm range.
O.S. 21XZ-B Features
- Fuel efficiency improved by 8% (compared to the 21XZ-B).
- Black-anodized cylinder head with reduced height (by 9mm, compared to O.S. Speed 21VZ-B V-Spec.II) plus additional holes for improved cooling and less weight.
- Lowered center of gravity for steadier car handling.
- Newly designed 21J2(B) three needle, double adjust carburetor with 6.5 aluminum restictor.
- Proven 3-port sleeve with special Speed version inner head and porting, for smoother, sharper acceleration.
- Strong, DLC-coated crankshaft with silicone-filled intake passage to improve fuel flow.
- Ceramic crankcase ball bearing.
- P3 glow plug.
O.S. 21XZ-B Specifications
Displacement: 3.49cc (0.213 cu in)
Bore: 16.3 mm (0.641 in)
Stroke: 16.8 mm (0.661 in)
RPM Range: 4,000-40,000
Power Output: 2.6 hp / 34,000 rpm
Weight: 355.0 g (12.52 oz)
Part #: OSMG2051 – 21XZ-B SPEED ABC 21J2(B)
Part #: OSMG2938 – T-2060SC WN TUNED SET
Part #: OSMG2939 – T-2060SC WN TUNED PIPE
Part #: OSMG2702 – M2000SC MANIFOLD
Part #: OSMG2701 – M2000 MANIFOLD