Spotlight: O.S.® 105HZ & 105HZ-R Heli Engines

These are the engines that precision aerobatic and 3D heli pilots have been waiting for! In order to nail huge maneuvers and smackdown-style 3D with your 90-sized machine your engine has to have power, and both the 105HZ and 105HZ-R deliver. Displacement has been increased by 15%, while a huge venturi rams air into the carburetor, producing massive power. Plus, they fit in a .91-sized mounting pattern. The machined, blue anodized heatsink head is light in weight, and cools the engine efficiently. An extra feature on the 105HZ-R is the pressurized DRS (Demand Regulator System), which ensures consistent fuel flow regardless of the heli's attitude.
Learn more about the O.S. 105HZ and 105HZ-R heli engines by visiting their product pages at
OSMG1960 105HZ
OSMG1961 105HZ-R
Displacement: 1.048 cu in (17.17 cc)
Bore: 1.442 in (29 mm)
Stroke: 1.024 in (26 mm)
Practical RPM: 2.000-16,500
Output: 3.8 ps @ 15,000 rpm
105HZ Weight: 21.03 oz (596 g)
105HZ-R Weight: 21.46 oz (608 g)
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