Everything you need to know about fuel-to-oil ratios
A 2-stroke ratio is the proportion of fuel to oil in your premix. For example, 50:1 means 50 parts gasoline mixed with 1 part two-stroke oil. This ratio ensures proper lubrication and engine protection.
The first number is fuel, the second is oil. So 50:1 means 50 parts fuel to 1 part oil. A lower first number (like 32:1) means more oil, while a higher number (like 100:1) means less oil in the mix.
If you're using AMSOIL (our recommendation):
Other common ratios:
AMSOIL's synthetic formula protects better at 50:1 than most conventional oils at richer ratios.
Yes, 50:1 is the most common ratio for modern two-stroke engines and is recommended by most manufacturers. It provides excellent protection with minimal smoke and carbon buildup when using quality synthetic oil.
Use 40:1 (or richer like 32:1) during engine break-in periods, with older engines, or when your manufacturer specifically requires it. Some vintage equipment and racing applications benefit from additional oil for extra protection.
Excess oil causes carbon buildup, fouled spark plugs, smoking exhaust, and reduced power. It can also clog exhaust ports and power valves over time. Always follow your manufacturer's recommended ratio or use proven alternatives like AMSOIL specifications.
No, ratios stay the same regardless of units. 50:1 is 50:1 whether you measure in liters and milliliters or gallons and ounces. Our calculator handles the unit conversion automatically while maintaining the correct ratio.
Always add oil to your container first, then add fuel. This ensures better mixing as the fuel agitates the oil. Shake or swirl the container gently to fully blend before fueling your engine.
AMSOIL SABER Professional is formulated and tested for 100:1 use in handheld equipment, cutting oil consumption by 50% while maintaining protection. Independent testing shows it outperforms competitive oils at 50:1. However, always follow your manufacturer's warranty requirements and use 100:1 at your own discretion.