An engine comprising: a cylinder; a carburetor configured to supply an air-fuel mixture into the cylinder and includes a throttle valve; and an ignition device configured to ignite the air-fuel mixture in the cylinder, wherein: the engine comprises: an engine-speed detecting unit configured to detect the speed of the engine; a throttle-opening detecting unit configured to detect the throttle opening of the carburetor; and a control unit configured to control the ignition timing of the ignition device; and during starting of the engine, if the throttle-opening detecting unit detects that the throttle opening is at a predetermined position and the engine has exceeded a predetermined speed, the control unit performs control such that: the ignition timing is retarded from a general angle to a first angle to a first angle and is maintained at the first angle for a predetermined number of cycles or time interval; and the retarded ignition timing is intermittently advanced from the first angle to a second angle and is maintained at the second angle for a predetermined number of cycles or time interval; said control is repeated until holding of the throttle opening at the predetermined position is released or the engine speed becomes less than the predetermined speed. a cylinder; a carburetor configured to supply an air-fuel mixture into the cylinder and includes a throttle valve; and an ignition device configured to ignite the air-fuel mixture in the cylinder, wherein: the engine comprises: an engine-speed detecting unit configured to detect the speed of the engine; a throttle-opening detecting unit configured to detect the throttle opening of the carburetor; and a control unit configured to control the ignition timing of the ignition device; and during starting of the engine, if the throttle-opening detecting unit detects that the throttle opening is at a predetermined position and the engine has exceeded a predetermined speed, the control unit performs control such that: the ignition timing is retarded from a general angle to a first angle to a first angle and is maintained at the first angle for a predetermined number of cycles or time interval; and the retarded ignition timing is intermittently advanced from the first angle to a second angle and is maintained at the second angle for a predetermined number of cycles or time interval; said control is repeated until holding of the throttle opening at the predetermined position is released or the engine speed becomes less than the predetermined speed. the engine comprises: an engine-speed detecting unit configured to detect the speed of the engine; a throttle-opening detecting unit configured to detect the throttle opening of the carburetor; and a control unit configured to control the ignition timing of the ignition device; and during starting of the engine, if the throttle-opening detecting unit detects that the throttle opening is at a predetermined position and the engine has exceeded a predetermined speed, the control unit performs control such that: the ignition timing is retarded from a general angle to a first angle to a first angle and is maintained at the first angle for a predetermined number of cycles or time interval; and the retarded ignition timing is intermittently advanced from the first angle to a second angle and is maintained at the second angle for a predetermined number of cycles or time interval; said control is repeated until holding of the throttle opening at the predetermined position is released or the engine speed becomes less than the predetermined speed. an engine-speed detecting unit configured to detect the speed of the engine; a throttle-opening detecting unit configured to detect the throttle opening of the carburetor; and a control unit configured to control the ignition timing of the ignition device; and during starting of the engine, if the throttle-opening detecting unit detects that the throttle opening is at a predetermined position and the engine has exceeded a predetermined speed, the control unit performs control such that: the ignition timing is retarded from a general angle to a first angle to a first angle and is maintained at the first angle for a predetermined number of cycles or time interval; and the retarded ignition timing is intermittently advanced from the first angle to a second angle and is maintained at the second angle for a predetermined number of cycles or time interval; said control is repeated until holding of the throttle opening at the predetermined position is released or the engine speed becomes less than the predetermined speed. the ignition timing is retarded from a general angle to a first angle to a first angle and is maintained at the first angle for a predetermined number of cycles or time interval; and the retarded ignition timing is intermittently advanced from the first angle to a second angle and is maintained at the second angle for a predetermined number of cycles or time interval; said control is repeated until holding of the throttle opening at the predetermined position is released or the engine speed becomes less than the predetermined speed.