How to Mix the Correct Fuel-Oil Ratio for Two-Stroke Engines

Two-stroke engines, commonly used in tools like disc cutters, chainsaws, and other power equipment, rely on a precise fuel-to-oil mixture for optimal performance. Mixing the correct ratio is essential to ensure the longevity of your engine, prevent damage, and maximize efficiency. In this guide, we’ll walk you through how to properly mix fuel and oil for two-stroke engines and highlight where you can find high-quality products to get the job done right.


Why Is the Fuel-Oil Mix Important?

Two-stroke engines don’t have a separate lubrication system like four-stroke engines. Instead, oil is mixed directly with fuel to lubricate the engine components during operation. An incorrect mix can lead to:

  • Too much oil: Excess smoke, fouled spark plugs, and carbon buildup.
  • Too little oil: Insufficient lubrication, causing overheating, excessive wear, and potential engine seizure.

Step-by-Step Guide to Mixing Two-Stroke Fuel

1. Check the Manufacturer’s Ratio Recommendation

Most two-stroke engines require a 50:1 or 40:1 fuel-to-oil ratio, but always refer to your tool’s manual for the exact specifications.

2. Use High-Quality Two-Stroke Oil

For the best results, choose a high-quality oil designed specifically for two-stroke engines. HTS Spares offers a range of oils to suit your needs:

3. Measure the Fuel and Oil Accurately

  • Use a clean, approved fuel container.
  • For a 50:1 ratio (common for modern tools), mix 100 ml of oil with 5 liters of unleaded petrol.
  • For a 40:1 ratio, mix 125 ml of oil with 5 liters of unleaded petrol.

Stihl’s one-shot oils, like the Stihl HP One-Shot 2-Stroke Mineral Oil (Pack of 10), make measuring simple and precise.

4. Mix Thoroughly

  • Pour half the petrol into the container.
  • Add the measured oil.
  • Seal the container and shake well to mix.
  • Add the remaining petrol and shake again to ensure even distribution.

5. Label and Store Safely

Always label the container with the mix ratio and the date. Store the mixture in a cool, dry place, and avoid using fuel older than 30 days.


Where to Buy Two-Stroke Oil and Accessories

HTS Spares has everything you need for mixing two-stroke fuel:


Final Tips

  • Always use fresh, high-octane unleaded petrol.
  • Clean your mixing container regularly to avoid contamination.
  • Never mix fuel directly in the tool’s tank.

By following these steps and using premium products from HTS Spares, you’ll keep your two-stroke engines running smoothly and efficiently. For more advice, feel free to contact us or explore our extensive range of products online!

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