O.S. has Updated the .25 SF with this New High-Performance .25 FX. This Engine can be utilized in Sport and Aerobatic Aircraft. The FX is made to Use a Muffler or Tuned pipeline. Includes a 2-Year Warranty.
FEATURES: Remote Needle Attached to the Backplate keeps hands 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 group 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 through the backplate to operate a vehicle washer
Width: 30mm(1.18") width of engine neglecting motor mounting flanges
38mm (1.50") distance between facilities associated with mounting holes
Height: 75.5mm (2.97")
Crankshaft Thread Size: 1/4-28
Recommended Props: Pattern Flying: 9X5, 9X6
Pattern Flying if a tuned pipeline is employed: 9.5X5
Sport Flying: 9X5, 9X6, 9.5X5, 10X4, 10X5
PracticalRPMNumber: 2,500 - 19,000 RPM
REQUIRES: longer Glow Plug (O.S. #8 recommended)
Fuel with 20percent (minimum) lubricant content and 5%-15% Nitromethane
(all of the 5%-15percent fuels we carry meet these requirements)
