An engine converts the reciprocating motion of the piston created by the force of combustion into rotary motion. When the force of combustion is greatest, some of that force pushes the piston
against the cylinder wall. This friction results in energy loss. An offset cylinder slightly shifts the conrod and piston
away from the center of the crankshaft, thereby reducing friction and using
the energy produced more effectively. This brings several benefits, like less weight,
more compactness and higher fuel economy.