Bourke engine

Despite finishing his design and building several working engines, the onset of World War II, lack of test results,[1] and the poor health of his wife compounded to prevent his engine from ever coming successfully to market.

The main claimed virtues of the design are that it has only two moving parts, is lightweight, has two power pulses per revolution, and does not need oil mixed into the fuel.

This causes the pistons to spend more time at top dead center than conventional engines.

The incoming charge is compressed in a chamber under the pistons, as in a conventional crankcase-charged two-stroke engine.

The operating cycle is very similar to that of a current production spark ignition two-stroke with crankcase compression, with two modifications: The following design features have been identified: The Bourke Engine has some interesting features, but the extravagant claims[14] for its performance are unlikely to be borne out by real tests.

Four-cylinder Bourke engine
Figure 2 from Patent US 2172670 A
Figure 1 from Patent US 2172670 A
Animation of a four-cylinder bourke engine