A 4-stroke dirt bike typically requires engine oil that is specifically formulated for motorcycles. The exact type and viscosity of oil can vary depending on the manufacturer's recommendations, so it's essential to consult the owner's manual of your specific dirt bike model for the correct information.
In general, most 4-stroke dirt bikes use a multi-grade oil, such as 10W-40 or 20W-50, which provides a balance between thinness at cold temperatures and thickness at high temperatures. These oils are designed to provide proper lubrication and protection for the engine, transmission, and clutch systems.
It's crucial to use motorcycle-specific oils rather than automotive oils because motorcycles have separate engine, transmission, and clutch components that require oils with specific frictional properties. Motorcycle oils are formulated to provide adequate lubrication for these components and maintain proper clutch operation.
Always refer to the manufacturer's guidelines to ensure you use the correct oil for your dirt bike to maintain its performance and longevity.