The 6-mode cycle was used in Japan for heavy-duty engines. It has been replaced by the newer 13-mode cycle and has only historical significance today.
The engine was tested over 6 different speed and load conditions. The modes were ran in sequence and the duration of each mode was 3 min. Emissions were measured at each mode and averaged over the cycle using a set of weighting factors. The final test result was expressed as volumetric concentration in ppm.
There were two definitions of the test modes and weighting factors: one for diesel engines and another one for gasoline and LPG engines. The diesel cycle parameters are listed in the table below.
|Mode||Speed (% of nominal)||Load (%)||Weighting factor|