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O.S. introduces two new 21XZ-R engines designed to overthrow the status quo in 1/8 scale on-road racing! Both can run a full 10-minute heat on just one tank of fuel, while most other engines need two tanks. That puts the 21XZ-R driver a pit stop ahead of the pack — and in sole possession of the lead to the checkered flag.
Engineered for added horsepower and faster lap times, the 21XZ-R Speed wowed the crowd at the 1/8 Scale On-Road Worlds in Miami, Florida. Team drivers turned in 4th and 5th place finishes with production models.
- Redesigned crankcase and carb produce smoother transitions and higher speeds
- The 21M slide-valve carb features 4 adjustable control settings, including a low-end metering needle for improved torque and fuel economy
- A more-balanced conrod reduces vibration and wear
Displacement: 3.49cc (.212 ci)
Bore: 16.27mm (.640 in)
Stroke: 16.8mm (.661 in)
Practical RPM: 4,000 to 45,000
Power Output: 2.8 ps/2.84 hp/33,000 rpm
Weight: 338g (11.9 oz)
Part #: OSMG2041 – O.S. Engines 21XZ-R on-road engine
Available early August!