#$%^&*AU2014200397A120140904.pdf#####ABSTRACT A combine harvester (102) drive system switches between a first isochronous operating curve (622) and a second isochronous operating curve (628) of an 5 isochronously governed engine (126) when a load on the combine harvester engine (126) reaches one or more threshold load conditions.LU 00 C14 NC "IN C"N - ----- -- -00. w In C>c 2 --a LO I I4 --- ----- --I / N N cc cc ~ / ... 2.~.. /cER cc o / , ii - -------------- --------------- ---------------T--------------- ----/E) cc: CS!~\ P-N anbi)