Rotary synchronous charge trapping

A two-stroke internal combustion engine, comprising:

• one or more cylinders, each cylinder comprising an exhaust port;
• one or more pistons positioned with the one or more cylinders, each piston configured to cyclically cover and uncover an associated exhaust port during reciprocation of the pistons within the cylinders;
• and
• one or more exhaust valves associated with each exhaust port, the exhaust valves being configured to rotate on an exhaust valve shaft around a valve axis that is substantially parallel to an axis of rotation of a crank shaft of the engine, each exhaust valve being configured to at least partially obstruct the associated exhaust port during a portion of the exhaust valve's rotation about the valve axis while the associated exhaust port is at least partially uncovered by the associated piston;
• wherein the one or more cylinders comprise at least two cylinders and the one or more exhaust valves comprise at least one exhaust valve associated with each of the cylinders, wherein the at least one exhaust valve associated with a first cylinder is angularly offset about the exhaust valve axis relative to the at least one exhaust valve associated with a second cylinder.