Beare Head

The Beare Head engine internal combustion engine technology combines a four stroke engine bottom end with a ported cylinder head closely resembling that of a two stroke, thus 4+2= six stroke^{[dubious – discuss]}. The head piston is smaller and has half the speed of the opposing piston. Functionally, the cylinder head piston replaces the valve mechanism of a conventional engine.

References

• www.sixstroke.com
• Australian Federal Court judgment
• costs judgment

first use of term "sixstroke" november_1994.pdf