The lambda sensor monitors the oxygen content of exhaust fumes and transmits the relative data instantaneously to the ECU. To ensure that the catalytic converters in the exhaust system work efficiently, the ECU controls fuel injection to maintain the air/fuel ratio within a tolerance close to the optimal value, achieving the minimum possible emissions of hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxide (NOx). The 3 way catalytic converters complete the exhaust fumes cleaning process by converting residues of CO, HC and NOX in the exhaust gas, thus ensuring exhaust emissions comply with EURO 3 regulations.
How to ensure that the catalytic converter functions correctly
In order to function correctly, the catalytic converter must reach a temperature of around 800°C and never fall below 300°C. The indicated maximum temperature must not be exceeded, otherwise the catalytic converter could be irreparably damaged. For this reason, it is essential that significant quantities of unburnt fuel do not accumulate in the exhaust gas post-treatment element, since these would otherwise burn resulting in a sharp increase in temperature. This is why the ignition-injection system should always be in perfect working order (misfiring is not acceptable). Moreover, the motorcycle should never be pushed with the ignition key and ENGINE STOP button set to ON. In this case, in fact, if the engine fails to start, the unburnt fuel will enter the exhaust system and deposit in the catalytic converters. Motorcycles fitted with catalytic converters must be used exclusively with unleaded petrol. Otherwise the lead content of petrol would deposit on the activated substances and limit their action against the harmful components of exhaust gas.