At bottom-dead-center (BDC) the inlet valve is closed and the compression stroke (b) starts. Work is done on the air/fuel mixture as the piston moves to TDC. In the vicinity of TDC the spark ignites ...

The position ... compression ratio program. We came up with a 4.00-inch bore, 3.48-inch stroke, a 64cc chamber and a piston with a roughly 2cc dome (it’s really bigger but once the valve reliefs ...

A patent for a six-stroke ... stroke position—reaches bottom dead center. Taking these attributes into account, we believe the concept works something like this: The intake, compression, and ...