O.S. Engine 91RZ-H Rear Exhaust Ringed Heli Engine  [OSMG1978]

Terrific news for the heli modelers: the most popular and effective .91 ringed motor now will come in a rear-exhaust design!

Pilots of Hirobo as well as other scale devices will appreciate the way the 91RZ-H energy plant will fit within the canopy to protect the heli's scale lines.

Like the side-exhaust 91SZ-H, the 91RZ-H features brand new intake porting, brand new carbohydrate and a redesigned crankcase that gives better help for the crank and thrust bearings.

Available with two temperature sink heads: a bigger, blue anodized mind for lots more efficient air conditioning or a more compact, squared die-cast head (DH).

SPECIFICATIONS

• Stock Numbers: OSMG1978 91RZ-H
• Displacement: 0.91 cu in (15 cc)
• Bore: 1.09 in (27.7 mm)
• Stroke: 0.98 in (24.8 mm)
• Practical rpm: 2,000-16,000
• Production: 3.3 hp @ 15,000 rpm
• Body weight w/o muffler: 21.3 oz (605 g)
• Includes: #8 radiance plug