What is the viscosity grade classification of motorcycle engine oil?
4 Answers
Four-stroke motorcycle engine oil viscosity grade classification: The winter oil grades in the SAE lubricating oil viscosity classification are: 0W, 5W, 10W, 15W, 20W, 25W. The symbol W stands for winter, and the smaller the number before W, the lower the low-temperature viscosity, the better the low-temperature fluidity, and the lower the applicable minimum temperature. The summer oil grades in the SAE lubricating oil viscosity classification are: 20, 30, 40, 50. The larger the number, the higher the viscosity and the higher the applicable maximum temperature. The all-season oil grades in the SAE lubricating oil viscosity classification are: 5W/20, 5W/30, 5W/40, 5W/50, 10W/20, 10W/30, 10W/40, 10W/50, 15W/20, 15W/30, 15W/40, 15W/50, 20W/20, 20W/30, 20W/40, 20W/50. The larger the number representing the summer part, the higher the viscosity and the wider the applicable temperature range. Two-stroke motorcycle engine oil viscosity grade classification: Two-stroke gasoline engine oil has two viscosity grades, namely SAE20 and SAE30. Generally, SAE30 is selected. If it is separate lubrication, used in cold regions, or for ultra-light load two-stroke engines, SAE20 is used.
The motorcycle oil viscosity grade classification, such as those number combinations under the SAE standard like 10W-40, has the first number like 10 representing low-temperature viscosity. The smaller this number, the smoother the winter startup. The 'W' stands for Winter, indicating the oil can quickly lubricate the engine in cold weather. The second number, like 40, indicates the viscosity at high temperatures, with higher numbers offering better protection in hot conditions. I prefer using 10W-40 for long-distance rides as it adapts to most climates, not becoming too thin in summer heat and ensuring smooth starts in winter. Choosing the wrong viscosity can lead to engine wear; for example, high viscosity may cause slow starts in cold regions, while low viscosity might offer insufficient protection in summer. Always refer to your motorcycle manual's recommendations and don't blindly follow online myths—this is crucial in maintenance.
Motorcycle oil viscosity grades are classified under the SAE system, such as codes like 20W-50. The number before the W indicates low-temperature performance, with 20 representing moderate viscosity during cold starts. The latter number, 50, reflects high-temperature performance, where a higher value signifies stronger heat resistance. Having worked on many bikes, I've observed that higher viscosity provides better protection for engine bearings in scorching heat, while lower viscosity ensures quicker starts in winter and better fuel efficiency. Oil selection should consider the environment—for instance, 15W-40 suffices in hot southern regions, whereas 10W is preferable for northern winters. Also, don’t overlook the efficiency of fresh oil, as old oil thickens and hampers heat dissipation. It’s advisable to check the dipstick every 5,000 km to ensure proper viscosity.
The SAE viscosity grade consists of several groups of numbers. The first part, such as 5W, indicates good cold-weather starting performance, while the latter part, like 30, refers to moderate viscosity in hot weather. When I was learning about motorcycles, I researched that W stands for Winter, meaning the viscosity decreases quickly at low temperatures, which is beneficial for engine lubrication. At high temperatures, a larger number indicates thicker oil, which protects components from wear. Beginners can opt for universal grades like 10W-40 or 15W-40. Maintaining the right viscosity can extend engine life and prevent friction losses.
