PURPOSE: To perform safe work of running stopping a running clutch lever, placed in a position halfway operation, to an on-position being associated with driving an engine by pulling to a control handle side an engine lever, for on-off operating an engine switch, to be turned and placed in an on-position area.

CONSTITUTION: When an engine is driven, an engine lever 3, for on-off operating an engine switch driving and stopping the engine, is pulled to a side of a control handle 4 from an off-position, turned and placed in an on-position area. Further by turning the engine lever 3 to be operated to the side of the control handle 4, a running clutch 5, placed in a position halfway disconnection, is stopped to an on-position of connection. Simultaneously, a running clutch is maintained in a position of connection, unless otherwise the engine lever 3 is returned in an opposite direction (opposite to a direction A), the running clutch lever 5 is not returned to a disconnection position (C). Thus only by controlling the engine lever 3 to be turned, driving and stopping of the engine and action of the running clutch can be attained.