ENGINE SYSTEM AND SADDLE-TYPE VEHICLE

During start-up of an engine, a reverse rotation start-up operation is performed in which a crankshaft is rotated in a forward direction after being rotated in a reverse direction. An engine unit is controlled such that the reverse rotation start-up operation is performed again, in a case in which a rotation state detected by a rotation state detector does not satisfy a predetermined start-up condition when the crankshaft is rotated in the forward direction in the reverse rotation start-up operation and before a piston reaches a first compression top dead center. A fuel injection device injects fuel such that a fuel-air mixture is introduced into a combustion chamber from an intake passage through an intake port in at least the first reverse rotation operation. An ignition device ignites the fuel-air mixture in the combustion chamber.