•  A multi side port system, which has intake and exhaust ports on the side housing, has been adopted.

•  The intake port is positioned on the side housing so that the port shape can be set freely. This eliminates overlap between the intake and exhaust ports, and prevents combustion gas from flowing into the intake process resulting in stable combustion.

•  There are two exhaust ports on one rotor. As a result, the expansion process is elongated for improved heat efficiency because retard of the opening timing on the exhaust port is enabled while keeping a sufficient exhaust port area, realizing both high engine output and low fuel consumption.

•  Intake air resistance has been greatly reduced by enlarging the intake port area. In addition, by retarding the closing timing of the intake port, intake air volume is increased for higher engine output.

•  Because the exhaust port equipped on the side housing allows unburnt gas to flow into the next combustion process, unburnt gas emission has been reduced.