OS Engines

O.S. 25FX ABL w/Muffler

25FX ABL w/Muffler

X-tra performance power for sport and competition!


O.S. Two Year WarrantyO.S. FX Series Engines feature dual bearings for durability and smooth operation, plus a low crankcase profile that allows for a proportionately taller, semi-squared head — a refinement that increases cooling fin area and improves heat dispersion. Plus, you'll never worry about losing a prop during flight — the threaded portion of FX crankshafts is extra-long to promote better engagement of the prop, nut and spinner and greater flight safety.
The high-speed needle valve on every FX engine is mounted remotely for added protection. An O-ring and ratchet spring minimize "creep" due to air leaks and vibration.

Specifications
Displacement: 4.07cc (.2485 cu in), Bore: 18mm (.708"), Stroke: 16mm (.630"), Horsepower: .84 BHP at 18,000 rpm, Weight: 248g (8.8oz) 10.8oz w/muffler, Practical rpm Range: 2,500 - 19,000 rpm, Recommended Props: Pattern Flying: 9x5, 9x6, Pattern Flying if a tuned pipe is used: 9.5x5, Sport Flying: 9x5, 9x6, 9.5x5, 10x4, 10x5