Four state-of-the-art >500 cc Euro 3 and one 150 cc Indian specification motorcycles were selected and evaluated over the Euro 3 and world harmonized WMTC test cycles for regulated pollutants and particles. The objectives of the work were to examine the correlation between emissions on the WMTC and Euro 3 cycles, to compare those results with previous work completed before the European WMTC limits were set, to examine particulate emissions, and to then evaluate the durability of one machine.
The correlation between Euro 3 and WMTC emissions results was used to extrapolate the appropriate level of WMTC limit values from the emissions limits on the Euro 3 test cycle. These WMTC extrapolated emissions limits were in line with the previous AECC motorcycle test program conducted in 2004 on Euro 2 motorcycles and also confirmed the appropriate level of the WMTC Euro 3 limits set in European Directive 2006/72/EC amending 97/24/EC.
As a result of these 2004 and 2008 test campaigns, two of the selected motorcycles were tested in both Euro 2 and Euro 3 versions, allowing for comparison of the emissions performance improvement realized by the motorcycle manufacturers.
Even though Euro 5 SI passenger car gaseous emissions limits are much lower than Euro 3 motorcycle levels, some of the tested bikes almost met them. All the bikes met the Euro 5 diesel passenger car particle number limit, after recalculation to give a NEDC equivalent value, despite sporadic rich operation giving higher particle numbers.
A further phase of work evaluated durability performance of a selected Euro 3 motorcycle. The durability exercise was cut short as both CO and NOx emissions exceeded the prescribed Euro 3 limits after only a couple of thousands of kilometers accumulated on a chassis dynamometer and had reached double the limit values well before the end of the durability period.