O.S. Engine OSMG0990 110FS-a Four-Stroke Performance Unit  [OSMG0990]

What the O.S. Engine OSMG0990 110FS-a brings to your model

The O.S. Engine 110FS-a Four-Stroke provides a meaningful power increase over the FS-91SII while keeping roughly the same dimensions. That 12.5% gain in output makes it a sensible choice for models needing more thrust without extra bulk.

Efficient blow-by recycling for lower maintenance

By redirecting blow-by into the lubrication system, the engine reduces friction and prolongs component life while cutting external oil deposits. This approach simplifies post-flight work and helps keep cowl interiors cleaner.

Adjustable F-5040 muffler for best fit and tone

The muffler can be rotated through 360 degrees, allowing neat exhaust routing on a variety of cowl shapes and producing a full, rich sound. The mounting bolt pattern matches the FS-91SII for easy interchangeability.

User-focused assembly and durability

The reversible carburettor and narrower camshaft housing aid installation and packaging. Enhanced tolerances and modernised internals reduce routine servicing, making this engine suitable for both sport and scale pilots.

The O.S. Engine 110FS-a Four-Stroke is well suited to model pilots who want strong four-stroke character, straightforward installation and reduced maintenance needs.