OS Motors .55HZ-R DRS Ring 40L-R

This is the Minimal Edition OS 55HZ-R DRS Ringed Helicopter Engine
with the DRS (Demand Regulator System).

FUNCTIONS:
DRS system provides fuel to the regulator under constant pressure
    for precise fuel delivery throughout the whole tank from complete to
    empty
Installing position of DRS is perfectly in line with the carb for
    constant operation in all attitudes of flight
Same installing bolt pattern as the OS 50SX-H Hyper
Double needle 40L-R carburetor enables independent change of idling,
    hovering and high speed with 4 arm throttle lever for use with
    a variety of servo brands
HZ Hyper low profile six fin cylinder head
2 year minimal service warranty through Pastime Provider starting at the
    date of purchase

CONSISTS OF:
OS 55HZ-R DRS Ringed Helicopter Engine, #8 Radiance Plug, Check Valve and
    User's manual

NEEDS:
10% to 30% nitro Fuel with a minimum of 18% lube (Helicopter Mix)
Fuel filter and beginning equipment

SPECIFICATIONS:
Engine;
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, Roughly two turns open from fully
closed position
    Idle Mix Control Screw, Factory set at center, turn ideal to
richen or delegated lean mix
    Medium Speed Needle Valve, One turn open from fully closed, adjust
only after setting high speed needle and idle mix screw, do
not turn more than 90° right or left
Distance/top of cylinder head-bottom of installing tabs: 2.8" (72.6mm)
Range between installing holes very same side: 0.68" (17.5mm)
Range between installing holes opposite side: 1.73" (44mm)
Range between muffler installing holes: 1.4" (37mm)
Cylinder Head Size: 1.8" (47mm)
Range/bottom of crankcase to top of cylinder head: 3.6" (90.9mm)
Range from center of engine to front bearing: 2.03" (51.6mm)
Range from center of engine to end of Crankshaft: 3.2" (82.6mm)
Range from center of engine to backplate bolt: 0.98" (25mm)
Distance from center of engine to throttle lever: 1.5" (38mm)