For the Yamaha Ray Z scooter, it is recommended to use a high-quality 4-stroke engine oil with the specification API SL or higher. Additionally, it is advisable to use the recommended viscosity grade, which is typically 10W-30 or 20W-40 for most riding conditions.
Regarding the frequency of oil changes, it is generally recommended to follow the manufacturer's guidelines provided in the owner's manual. The recommended oil change intervals can vary depending on factors such as riding conditions, climate, and the type of oil used. Typically, for most motorcycles and scooters, an oil change is recommended every 3,000 to 5,000 kilometers or every 6 months, whichever comes first. However, it's always best to consult the owner's manual for the specific recommendations for your Yamaha Ray Z scooter.
Regular oil changes are crucial for maintaining the engine's performance and longevity, so it's important to adhere to the manufacturer's recommended intervals. If you frequently ride in harsh or extreme conditions, such as dusty or hot environments, you may need to change the oil more frequently to ensure optimal lubrication and protection for the engine.