
07/29/2011
By Mike Garrison
LiveRC.com
O.S. is proud to announce their all-new 21XZ-R on-road engines. With the standard and Speed models available, we look forward to seeing these hit the track upon their release this August!
OFFICIAL O.S. ENGINES PRESS RELEASE:
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
Specifications:
- Displacement: 3.49 cc (.212 ci)
- Bore: 16.27 mm (.640 in)
- Stroke: 16.8 mm (.661 in)
- Practical RPM: 4,000 to 45,000
- Power Output: 2.8 ps/2.84 hp/33,000 rpm
- Weight: 338 g (11.9 oz)
Equipped with many of the same performance features as the .21XZ-R Speed ABC, the 21XZ-R VII offers explosive acceleration and top-end for race-winning potential at a more economical price.
- Combines aggressive timing with easy starting so drivers can unleash its race-winning potential right out of the box
- The cylinder liner boasts 7 scavenger ports and three exhaust ports
Specifications:
- Displacement: 3.49 cc (0.213 ci)
- Bore: 16.27 mm (.640 in)
- Stroke: 16.8 mm (.661 in)
- Practical RPM: 4,000 to 45,000
- Power Output: 2.8 ps/2.84 hp/33,000 rpm
- Weight: 343 g (12.1 oz)
OSMG2041 .21XZ-R Speed ABC Retail:$799.99 Street:$499.99
OSMG2042 .21XZ-R VII On-Road Retail:$699.99 Street:$399.99






