Tests for gasoline, diesel and motorcycles

During the exhaust emissions test, the various pollutants and gases that are still coming out of the exhaust are measured. For petrol engines, these are CO, HC, O2 and NOx, which are measured at idling speed and at increased engine speed. A probe is inserted into the exhaust for this purpose. Certain gases may only be present in the exhaust gas in specific, percentage-based quantities.

The diesel engine mainly produces soot particles. Their density is determined by measuring the smoke opacity during free acceleration and must not exceed a certain opacity factor (K value).

The engine temperature, engine speed and carbon monoxide (CO) content in the exhaust gas are measured during the exhaust emission test on the motorcycle (AUK). Furthermore, it is determined whether the mixture preparation and the exhaust system comply with the homologated components and are in perfect condition. For motorcycles without or with an unregulated catalytic converter, the CO value is determined at idling speed. Unless otherwise specified by the manufacturer, a maximum of 4.5 vol% CO may be reached. For motorcycles with a regulated catalytic converter, it is assessed at an increased idling speed (approx. 2,000 rpm). If the manufacturer has not specified any AUK values, a maximum of 0.3 vol% CO may be achieved.