Engine control method and device for small vehicles or motorcycles

Two embodiments of engine speed control that avoid undesirable vehicle conditions such as wheel slippage or unintentionally performing a wheelie. This is done by sensing actual conditions, which are likely to result in the undesirable vehicle conditions and only changing the engine output when these exact conditions are found. The conditions sensed are the determination of excessive acceleration in engine speed or in the speed of a shaft associated with the engine or the degree of rotational variation or rotational acceleration.