O.S. Engine 91HZ  [OSMG1975]

With back-to-back FAI world championships in 2005 and 2007, the 91SZ-H was a success by anyone's standards. Now there's the 91HZ ?V a 91SZ-H redesigned aided by the information worldwide's top pilots. It gives the tuning simplicity and gratification consistency regarding the multi-time world champ and design innovations that promote improved air conditioning, a tighter compression seal ?V and tuning simplicity!

The slim profile associated with heat sink mind helps the 91HZ fit completely inside cooling shrouds without cutting or losing cooling energy!
Two temperature sinks ?V one regarding head, another in the crankcase ?V allow airflow to hold away warm and continue maintaining performance.
Better overall stability reduces motor noise and encourages smoother, stronger performance.
The latest 61B carb takes persistence to another location level. Dependability features start with an insulating ring which stops crankcase temperature from affecting carb settings. a nice usage of O-ring seals ?V two on the primary needle, one on rotor ?V prevents air leaks and power fluctuations.
In-flight control of needle valve guarantees smooth, consistent runs.

Specs:

• Inventory Quantity: OSMG1975
• Displacement: 0.912 cu in (14.95 cc)
• Bore: 1.091 in (27.7 mm)
• Stroke: 0.976 in (24.8 mm)
• Weight: 21.8 oz (618 g)
• Practical RPM Range: 2,000-16,000
• Production: 3.4 hp @ 15,000 rpm
• Includes: 61B carburetor, muffler, in-flight needle valve modification arm & #8 radiance plug