25FX O.S. Engine Non-Ringed W/Muffler

O.S. has Updated the .25 SF with this New High-Performance .25 FX. This Engine may be used in Sport and Aerobatic Aircraft. The FX is Designed to Use a Muffler or Tuned Pipe. Comes with a 2-Year Warranty.

 

FEATURES: Remote Needle Attached to the Backplate keeps fingers away from prop

          Twin Ball Bearing-Supported Crankshaft

          Schnuerle Porting (Schnuerle scavenging)

          Non-Ringed (ABN) Construction

          Side Exhaust

          One-Piece Crankcase

 

INCLUDES: One Expansion Style Muffler

          One Set of Instructions, Decal, and Poster

          One Assembled .25 FX w/Carb

 

SPECS:    Displacement:  4.07cc (.2485 cu in)

          Bore: 18.0mm (.708″)

          Stroke: 16.0mm (.630″)

          Horsepower: .84 BHP at 18,000 RPM

          Weight: 248g (8.8oz)  10.8 oz w/muffler

          Length: 75.6mm (2.98″) distance from the backplate to drive washer

          Width: 30mm(1.18″) width of engine neglecting engine mounting flanges

                 38mm (1.50″) distance between centers of the mounting holes

          Height: 75.5mm (2.97″)

          Crankshaft Thread Size: 1/4-28

          Recommended Props: Pattern Flying: 9X5, 9X6

            Pattern Flying if a tuned pipe is used: 9.5X5

            Sport Flying: 9X5, 9X6, 9.5X5, 10X4, 10X5

          Practical RPM Range: 2,500 – 19,000 RPM

 

REQUIRES: Long Glow Plug (O.S. #8 recommended)

          Fuel with 20% (minimum) lubricant content and 5%-15% Nitromethane

            (All the 5%-15% fuels we carry meet these requirements)