O.S. FR5-300 Sirius

This incredible 50cc, five cylinder radial engine closely follows full-size practice in its design and construction, including the use of a geared double-track cam ring to operate its valve gear.

The Sirius features pushrod driven overhead valves, four ball bearings & two needle bearings, ringed pistons, a special inlet manifold assembly to balance the mixture distribution to the inlet pipes from the carburettor and a special propeller locknut assembly as standard.

Supplied complete with a radial mount, the FR5-300 Sirius is ideal for large scale models and is designed to be used with 18\" x 12~14\" to 22\" x 8\" propellers.

See the engine accessories at the end of this section for the optional front or rear exhaust collector rings specifically designed for this engine.