O.S. 55HZ-R w/Powerboost Pipell Limited Edition Engine

Tower Stock# LXBWGN  •  Manufacturer Stock# 15654
Notes from our tech department:
This is the Limited Edition OS 55HZ-R DRS Ringed Helicopter Engine
with the PowerBoost Pipe.


Mounting position of DRS is perfectly in line with the carb for
consistent operation in all attitudes of flight
Same mounting bolt pattern as the OS 50SX-H Hyper
Dual needle 40L-R carburetor allows independent adjustment of idling,
hovering and high speed with four arm throttle lever for use with
a variety of servo brands
HZ Hyper low profile six fin cylinder head
PowerBoost pipe offers excellent performance from high RPM
manuevers to idling and hovering, polished natural finish aluminum
Two year limited warranty through Hobby Services beginning at the
date of purchase


OS 55HZ-R DRS Ringed Helicopter Engine, 8 Glow Plug, Check Valve,
PowerBoost Pipe with Pressure Nipple, Mounting Hardware, Exhaust
Tube and Instruction Manual


10 to 30 nitro Fuel with at least 18 lubricant (Helicopter Mix)
Fuel filter and starting equipment


Displacement: 0.55 cu in (8.93cc)
Bore: 0.91 (23mm)
Stroke: 0.85 (23.5mm)
Practical RPM: 2,000-20,000 RPM
Output: 2.1 PS, 2.07 HP
Weight: 15.1oz (429g)
Carburetor Settings:
High Speed Needle Valve, Approximately two turns open from fully
closed position
Idle Mixture Control Screw, Factory set at center, turn right to
richen or left to lean mixture
Medium Speed Needle Valve, One turn open from fully closed, adjust
only after setting high speed needle and idle mixture screw, do
not turn more than 90 right or left
Powerboost Pipe II Specs,
Length: 10.4 (264mm)
Diameter: 1.8 (45mm) at engine attachment point
Distance Between Mounting Hole Centers: 1.5 (37.5mm)
Engine Dimensions,
Distancetop of cylinder head-bottom of mounting tabs: 2.8 (72.6mm)
Distance between mounting holes same side: 0.68 (17.5mm)
Distance between mounting holes opposite side: 1.73 (44mm)
Distance between muffler mounting holes: 1.4 (37mm)
Cylinder Head Diameter: 1.8 (47mm)
Distancebottom of crankcase to top of cylinder head: 3.6 (90.9mm)
Distance from center of engine to front bearing: 2.03 (51.6mm)
Distance from center of engine to end of Crankshaft: 3.2 (82.6mm)
Distance from center of engine to backplate bolt: 0.98 (25mm)
Distance from center of engine to throttle lever: 1.5 (38mm)

jxs 122310



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