.55HZ-H Hyper Ring 40L 

This is the OS 55HZ Hyper Ringed Helicopter Engine with the 40L Carburetor. FEATURES: Ideal for 3D flight-power equal to .60 size heli engines Same mounting bolt pattern and silencer size as the OS 50SX-H Hyper Dual needle 40L 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 black aluminum six fin cylinder head Two year limited warranty through manufacturer beginning at the date of purchase INCLUDES: OS 55HZ Hyper Ringed Helicopter Engine with 40L Carburetor, #8 glow plug and instruction manual REQUIRES: 10% to 30% nitro Fuel with at least 18% lubricant (Helicopter Mix) Exhaust system such as the OS PowerBoost Pipe, OSMG2880 Starting equipment SPECS: Displacement: 0.55 cu in (8.93cc) Bore: 0.91" (23mm) Stroke: 0.85" (23.5mm) Practical RPM: 2,000-17,000 RPM Weight: 14.39oz (408g) Carburetor Settings: High Speed Needle Valve, Two turns open from fully closed Idle Mixture Control Screw, Factory set-do not adjust Medium Speed Needle Valve, Two turns open from fully closed Distance/top 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) Distance/bottom 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)