Yamaha YZ450FJ YZ450F 2018 Owner's Manual
![Yamaha YZ450FJ YZ450F 2018 manual cover](/images/6c038534f11802e0c8e96710/thumbs/thumb175x175.webp)
To break in the engine, start with short periods of moderate riding. Avoid full throttle and vary the engine speed. After the first hour, change the oil and oil filter to remove any metal particles. Gradually increase the engine load over the next few hours of riding.
The recommended oil is Yamalube 4-R 10W-50 or a high-quality 4-stroke motorcycle oil with an API service classification of SG or higher. Always check the owner's manual for the manufacturer's latest recommendations.
The air filter should be checked and cleaned after every ride in dusty conditions. In less severe conditions, inspect it at least every 2-3 rides. Replace the air filter if it's damaged or excessively dirty.
The recommended tire pressure is typically around 12 psi for the front and rear tires. However, this can vary based on riding conditions and personal preference. Always check the tire pressure before each ride.
Adjust the suspension by tuning the compression and rebound damping settings. Start with the factory settings, then make small adjustments to suit your riding style and track conditions. Refer to the owner's manual for specific guidance on making these adjustments.
First, check the fuel level and ensure the fuel valve is on. Verify that the kill switch is in the 'run' position. Inspect the spark plug for fouling or damage and replace it if necessary. If the bike still won't start, it may require professional diagnosis.
To change the coolant, first, ensure the engine is cool. Remove the radiator cap and drain bolt to let the old coolant out. Flush the system with distilled water, then refill with a 50/50 mix of coolant and distilled water. Bleed any air from the system by running the engine with the radiator cap off until warm.
Signs of clutch wear include slipping under load, difficulty in shifting gears, or a spongy clutch lever feel. If you notice these symptoms, inspect the clutch plates and springs, and replace them if worn.
To adjust the chain tension, place the bike on a stand, loosen the axle nut, and turn the chain adjuster bolts evenly until the chain has 1-1.5 inches of slack at the midpoint. Tighten the axle nut to secure the adjustment.
After riding in wet or muddy conditions, thoroughly clean the bike to remove dirt and moisture. Check and lubricate the chain, inspect the air filter for dirt, and ensure all electrical components are dry and functioning properly.