The main function of the oil filter is to adsorb and filter impurities such as iron filings in the oil to prevent them from entering the engine again to participate in friction and cause wear. The air filter element is also called an air filter. Its main function is to filter impurities in the engine intake air. It is like putting a mask on the engine to filter out particulate matter in the air.

   Replacement cycle: Generally 5-7k kilometers, determined according to local air quality. For example, the maintenance cycle is different between riding in the desert every day and riding in the city every day. Since the maintenance cycle of straddle-mounted (geared) motorcycles is long, they must be maintained together with the engine oil and engine filter.