This is the O.S. Engines 91 HZ-R 3D Speed Helicopter Engine in Black with the 91 PowerBoost Tuned Pipe. ****** Because of the competition nature of this engine,...More

This is the O.S. Engines 91 HZ-R 3D Speed Helicopter Engine in Black with the 91 PowerBoost Tuned Pipe. ****** Because of the competition nature of this engine,****** ******it is NOT covered by the O.S. 2 Year Warranty.****** Carburetor Adjustments- High Speed Needle Valve: Turn approximately 30¦ (3-4 clicks) during initial adjustments, then approximately 15¦ (1-2 clicks) when making final adjustments Medium Speed Needle Valve: Turn approximately 30¦ (3-4 clicks) at a time Idle Mixture Control Screw: Turn approximately 5¦ at a time, turn left to enrich idle mixture and right to lean mixture Height from crankcase bottom to top of cylinder head: 3.9 (100mm) Height/bottom of mounting tab to top of cylinder head: 3.1 (79mm) Distance between mounting holes same side: 0.98 (25mm) Distance between mounting holes opposite side: 2 (52mm) Distance between muffler screw holes: 1.6 (42mm) Distance/bottom of mounting tab to muffler screw holes: 1.8 (42.8mm) Distance throttle lever to center of engine: 1.6 (42mm) Length from front bearing to center of engine: 2.2 (56.4mm) Length from front bearing to backplate: 3.3 (83.8mm) Length from backplate to end of crankshaft: 4.6 (118mm) Length from backplate to center of engine: 1.1 (27.4mm) Width of crankcase below mounting tabs: 1.7 (43mm) Width between mounting tabs: 2.4 (61mm) Pipe- Length: 12.3 (313mm) Diameter: 2.0 (50mm) at engine attachment point Exhaust Outlet Diameter: 0.20 (5mm) Weight: 7.9oz (225g) jxs 04/08/11 ir/jxsLess