2015 Yamaha MT125 — Owner's Manual
Replacing the air filter element and cleaning the check hose The air filter element should be replaced at the intervals specified in the periodic maintenance and lubrication chart. Have a dealer replace the air filter element more frequently if you are riding in unusually wet or dusty areas. In addition, the air filter check hose must be frequently checked and cleaned if necessary. The valve clearance changes with use, resulting in improper air-fuel mixture and/or engine noise.
To prevent this from occurring, the valve clearance must be adjusted by a dealer at the intervals specified in the periodic maintenance and lubrication chart. Tires are the only contact between the vehicle and the road. Safety in all conditions of riding depends on a relatively small area of road contact. Therefore, it is essential to maintain the tires in good condition at all times and replace them at the appropriate time with the specified tires.