Method for controlling the fuel supply to an internal combustion engine at start-up and a carburettor

A method of controlling a fuel supply to be rich or lean in a carburetor during a start attempt of an internal combustion engine, the carburetor having a fuel supply system configured to be set in a lean mode or a rich mode, the rich mode providing extra fuel during the start attempt, the method comprising:

• a) during the start attempt, determining if a subsequent start attempt should be executed in the lean mode or the rich mode in response to an evaluation of at least one engine parameter from a previous start attempt, a run of the engine, or the start attempt, wherein the evaluation of the at least one engine parameter from the previous start attempt, the run of the engine, or the start attempt comprises determining if an ignition indication occurred in the start attempt;
• and
• b) setting the fuel supply system in the rich mode or the lean mode for the subsequent start attempt in response to the evaluation of the at least one engine parameter from the previous start attempt, the run of the engine, or the start attempt, wherein if an ignition indication is determined to have occurred, the fuel supply system is set or maintained in the lean mode.