Historical design Dugald Clerk developed the first two cycle engine in 1879.
It used a separate cylinder which functioned as a pump in order to transfer the fuel mixture to the cylinder.6 In 1899 John Day simplified Clerk's design into the type of 2 cycle engine that is very widely used today.13 Day cycle engines are crankcase scavenged and port timed.The crankcase and the part of the cylinder below the exhaust port is used as a pump.
The operation of the Day cycle engine begins when the crankshaft is turned so that the piston moves from BDC upward (toward the head) creating a vacuum in the crankcase/cylinder area.
There are cast in ducts from the crankcase to the port in the cylinder to provide for intake and another from the exhausst port to the exhaust pipe.
When the piston rose close to TDC a spark ignites the fuel.
As the piston is driven downward with power it first uncovers the exhaust port where the burned fuel is expelled under high pressure and then the intake port where the process has been completed and will keep repeating. Later engines used a type of porting devised by the Deutz company to improve performance.
It was called the Schnurle Reverse Flow system.
Their DKW RT 125 was one of the first motor vehicles to achieve over 100 mpg as a result.14Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine
Some systems disable alternator field (rotor) power during wide open throttle conditions. Disabling the field reduces alternator pulley mechanical loading to nearly zero, maximizing crankshaft power..In this case the battery supplies all primary electrical power. Gasoline engines take in a mixture of air and gasoline and compress it by the movement of the piston from bottom dead center to top dead center when the fuel is at maximum compression.The reduction in the size of the swept area of the cylinder and taking into account the volume of the combustion chamber is described by a ratio.Early engines had compression ratios of 6 to 1.As compression ratios were increased the efficiency of the engine increased as well. With early induction and ignition systems the compression ratios had to be kept low.
With advances in fuel technology and combustion management high performance engines can run reliably at 12:1 ratio.With low octane fuel a problem would occur as the compression ratio increased as the fuel was igniting due to the rise in temperature that resulted. Charles Kettering developed a lead additive which allowed higher compression ratios. The fuel mixture is ignited at difference progressions of the piston in the cylinder.At low rpm the spark is timed to occur close to the piston achieving top dead center.In order to produce more power, as rpm rises the spark is advanced sooner during piston movement.The spark occurs while the fuel is still being compressed progressively more as rpm rises.18Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine