O.S.Speed 91HZ-R 3D Helicopter Engine
O.S.Speed 91HZ-R 3D Helicopter Engine
O.S.Speed 91HZ-R 3D Helicopter Engine
O.S.Speed 91HZ-R 3D Helicopter Engine
O.S.Speed 91HZ-R 3D Helicopter Engine
O.S.Speed 91HZ-R 3D Helicopter Engine

O.S.Speed 91HZ-R 3D Helicopter Engine

$479.99 $649.99
Coming Soon
SKU: OS-18642

Following the popularity of the 91HZ-R with on-demand regulator, O.S. has now taken high-performance, high-speed helicopter engines to the next stage of evolution. 

Features:

  • Lightweight, machined heat sink head
  • Big-bore carburettors best-suited for the intended use (F3C or 3D)
  • Best precision advanced exhaust cylinder timing (for F3C or 3D)
  • Newly designed combustion chambers, shaped to match the big bore carburetors and advanced exhaust cylinder timing
  • Lightweight, forged steel crankshaft counter weight to lower vibration for higher speeds
  • Improved back plate shape, to accommodate Futaba's BPS-1 RPM Sensor and increase primary pressure for greater stability
  • The cover plate has a cell to accept a sensor designed to install in the cover plate from Futaba GY701 / CGY750 Governor

Technical Specifications:

  • Displacement: 14.95cc
  • Bore: 27.7mm
  • Stroke: 24.8mm
  • Output: 3.6ps/15,500RPM
  • Practical RPM Range: 2,000-16,500
  • Weight: 603g

Package Includes:

  • Engine Pack O.S. Speed Tuned .91HZ-R Helicopter Engine with Pump, 61G Carb
  • #8 Glow Plug
  • Check Valve
  • Head Gasket 0.2mm
  • OS Speed Decal and English Instruction Manual