The Wyvern - E T Westbury
The Wyvern is a horizontal, open crank stationary engine of the type that played a very important role in the mechanisation of industry.
Otto cycle engines, burning gas or petrol, rapidly replaced steam plant for small and medium sized applications from around 1880 onwards. The first Otto engines borrowed many of their structural features from contemporary steam engine practice, including the open horizontal frame of the orthodox mill engine. Crossely Brothers, the UK licensees of the Otto patents, were responsible for a number of important improvements including poppet valves and the clerestory combustion chamber. Westbury included all of these features in the Wyvern which was designed and launched in 1963.
With a displacement of 40cc, the Wyvern was designed to run at a constant 1,500 - 2,000rpm. Lubrication is from 3 wicked oil cups and the cylinder is water cooled. The completed engine measures 12" x 8" x 6" wide across its two Ø6½" iron flywheels. The generous proportions (Bore x Stroke = Ø1¼" x 2") and simplicity of the open crank design allow this to be recommended as an engine project for new comers. With a majority of its workings exposed, it must also be said that a running Wyvern engine provides much eye-appeal!
The Wyvern in Action