O.S. 55HZ-R DRS Ringed Heli

State-of-the-art power for serious heli pilots!

The 55HZ-R DRS Ringed delivers state-of-the-art power for serious heli pilots! It includes the Demand Regulator System for outstanding run consistency and a built-in mount for Futaba GY701 and CGY750 rpm sensors. Two needles on the included 40-LR carb let pilots precisely adjust middle and high speeds.
Displacement: 0.55 in3 (8.9 cc), RPM Range: 2,000-20,000, Output: 2.1 hp @ 17,000 rpm, Weight: 15.1 oz (429 g) Requirements: 10%-30% nitro heli fuel with a minimum 18% lubricant content, Starting equipment

O.S. Two Year Limited Warranty
  • Includes: #8 plug, 40-LR carb & check valve.
  • 2-year limited Hobby Services warranty.
  • The Demand Regulator System (DRS) uses pressure to consistently deliver the optimal air-fuel mixture to the engine — regardless of the heli's attitude.
  • Two needles on the carburetor precisely adjust middle and high speeds.
  • A hole in the cover plate allows for mounting an rpm sensor for the Futaba® GY-701 governor or CGY750 gyro, ensuring precise rpm control.
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