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O.S. FS-81-a .81 Four Stroke Glow Engine w/Muffler

With your purchase, receive at no cost:
This is the OS Engines 81FS-a four stroke ring engine, with 60RA carburetor and included OS F5030 muffler.  Packing more power into 60-size planes!

  • Mounts easily in the same space as the FS-70SII with no modifications.
  • A rubber O-ring on the muffler's multi-positional manifold helps prevent oil leakage.
  • The specially designed lubrication system eliminates the need for crankcase ventilation.
  • The 60RA carburetor is equipped with a venturi that reduces the chance of fuel leaking out onto the cowl, while also creating more positive air/fuel flow.


  • Displacement: 0.809 cu in (13.26 cc)
  • Bore: 1.091 in (27.7 mm)
  • Stroke: 0.866 in (22.0 mm)
  • Weight w/muffler: 19.63 oz (556 g)
  • Practical rpm range: 2,200-12,000
  • Output: 1.3 hp @ 11,000 rpm

This product was added to our catalog on February 11, 2009.

List Price: $599.99
You Save: $230.00 (38%)
Price: $369.99
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