Over two years in the making, the GT55 offers 20-30% more power than any other engine in its class — plus the high-quality fit and finish that distinguishes the entire O.S. lineup. The front mounted Walbro® carb ensures instantaneous throttle control and consistent fuel flow at all times. The O.S. IG-01 electronic ignition system adjusts timing automatically and assures quick starts by compensating for wet plugs. The system also signals low-voltage conditions.
The front-induction, rotary-valve crankshaft, coupled with the IG-01 ignition, deliver optimum timing at any throttle setting. Other performance advantages include right-left throttle lever mounting, a factory-installed diaphragm vent nipple, massive front/rear bearings and more.
In this video Steve Kaluf gives you a guided tour of the GT55 gas engine's features. You'll also see the engine in action, demonstrating its effortless starts and incredible power when installed on the beautiful Great Planes Pitts M-12s. This 55cc powerhouse is the first gas engine from O.S. — and it easily lives up to the quality and performance standards that have made the O.S. brand famous worldwide!
For complete information about the GT55 gas engine, visit its product page at .
Additional features:
• Ringed, lightweight aluminum-alloy piston
• 1-piece crankcase
• Front-induction, rotary-valve crankshaft
• Insulator between the crankcase and carb
• 2-year limited warranty
OSMG1555
Displacement: 3.352 cu in (54.9 cc)
Bore: 1.618 in (41 mm)
Stroke: 1.618 in (41 mm)
Output: 5.5 hp @ 7,000 rpm
Practical RPM: 1,500-8,000
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