Yamaha YZ125P1 2002 Owner's Manual

The recommended oil-to-fuel ratio for the Yamaha YZ125P1 2002 is 32:1. This means mixing 32 parts of fuel with 1 part of 2-stroke oil.
It is advisable to clean the air filter after every 2-3 rides, or more frequently if you are riding in dusty or muddy conditions.
The recommended spark plug for the Yamaha YZ125P1 2002 is NGK BR9EG or an equivalent.
To adjust the chain tension, loosen the axle nut, use the chain adjusters to set the proper tension, ensuring there is about 1.2 inches (30 mm) of slack, then retighten the axle nut.
The recommended tire pressure for the Yamaha YZ125P1 2002 is approximately 12 psi for the front tire and 12-15 psi for the rear tire.
Check the spark plug for fouling, ensure the fuel is fresh, verify the carburetor is clean, and inspect the ignition system for faults.
Improving suspension performance can be achieved by adjusting the fork and shock settings according to your weight and riding style, and ensuring regular maintenance.
Regular maintenance includes cleaning the air filter, checking and changing the spark plug, adjusting the chain, lubricating moving parts, and changing the transmission oil.
To bleed the brakes, attach a clear tube to the brake caliper's bleed screw, pump the brake lever, hold it, open the bleed screw to release air/fluid, close the screw, and repeat until no air bubbles appear.
Common issues include worn-out spark plugs, clogged carburetors, chain and sprocket wear, and suspension component degradation. Regular maintenance can help prevent these issues.