Yamaha RST90X, RST90GTX 2008 Owner's Manual
![Yamaha RST90X, RST90GTX 2008 manual cover](/images/39a254b039fb4526fc5bb114/thumbs/thumb175x175.webp)
The recommended oil type for the 2008 Yamaha RST90X is Yamalube 4, 10W-40 or any high-quality, 4-stroke motor oil equivalent.
It is advisable to check and replace the spark plugs every 3,000 miles or once a year, whichever comes first, to ensure optimal performance.
First, check the fuel level and battery condition. Ensure the kill switch is in the 'run' position and inspect the spark plugs for fouling.
To winterize, drain the fuel system, add a fuel stabilizer, change the oil, lubricate moving parts, and store in a dry, covered location.
Remove the air filter and gently clean it with compressed air. If it's very dirty, wash with warm soapy water, rinse, dry, and re-oil lightly.
Adjust the suspension by changing the preload settings on the front forks and rear shock absorber to match your weight and riding conditions.
Inspect the air filter, fuel injectors, and throttle body for dirt or clogs. Ensure tires are properly inflated and check for any engine error codes.
Ensure the brake pads are not worn out, check and bleed the brake fluid system, and make sure the brake discs are clean and not warped.
The recommended tire pressure is typically 32 psi for the front tire and 36 psi for the rear tire, but always refer to the owner's manual for specifics.
Check the coolant level and radiator for blockages, ensure the thermostat is functioning, and inspect the water pump and hoses for leaks.