| 主权项 |
1. A method for selectively reducing power of a two-stroke engine having at least one piston movable in a cylinder and an exhaust port, the method comprising:
providing an exhaust valve in communication with the exhaust port of the engine, the exhaust valve having an adjustable position to change an effective size of the exhaust port; sensing a condition likely to cause damage to the piston of the engine; signaling the condition likely to cause damage to the piston of the engine; and adjusting a state position of the exhaust valve to reduce a size of the exhaust port in response to sensing the condition likely to cause damage to the piston of the engine, thereby limiting power of the engine, by:
measuring fault events at a manifold pressure sensor, a detonation sensor, a valve position sensor, an exhaust temperature sensor, and an engine water temperature sensor;adjusting, selectively, a position of the exhaust valve to one of a plurality of incremental positions between an up state position, at least one middle state position, and a down state position to fine tune the effective size of the exhaust port and limit the power of the engine, and the at least one middle state position is located between the up state position and the down state position;evaluating a severity of the sensed condition;adjusting the state position of the exhaust valve if the severity of the sensed condition exceeds a predetermined severity threshold;incrementally adjusting the position of the exhaust valve without changing a current state position of the exhaust valve if the severity of the sensed condition is below the predetermined severity threshold; anddetermining whether a first predetermined number of fault events occur within a first predetermined time period and adjusting the state position of the exhaust valve to reduce the size of the exhaust port if the first predetermined number of fault events occur within the first predetermined time period, whereinincrementally adjusting the position of the exhaust valve includes determining whether a second predetermined number of fault events occur within a second predetermined time period and incrementally adjusting the state position of the exhaust valve without changing the current state position of the exhaust valve if the second predetermined number of fault events occur within the second predetermined time period. |
