Two-stroke engines rely on a mixture of gasoline and engine oil to lubricate internal parts like pistons, bearings, and crankshafts. Without oil, these parts will dry out, overheat, or wear out quickly.
An 80:1 Premix Ratio Means
80 parts gasoline to 1 part two-stroke engine oil
This mix ratio is commonly used in modern portable equipment to improve clean performance and reduce exhaust emissions.
Why Choose an 80:1 Ratio?
An 80:1 oil mixture offers the following benefits:
- Reduced emissions and odor
- Cleaner spark plugs and exhaust systems
- Smoother performance using high-quality synthetic oil
- Greater fuel economy than using a thicker mixture
Suitable for
- Lawn mowers / trimmers
- Grass trimmers
- Leaf blowers
- Hedge trimmers
Small two-stroke multi-tools
Important note: Always follow the equipment manufacturer’s recommended mixing ratio. How to calculate an 80:1 fuel mix.
The Formula is Simple:
Volume of fuel ÷ 80 = volume of oil required
For example
4 liters of gasoline → 50 ml of oil
The following table makes the calculation easy
80:1 Premix Fuel Mix Chart
Metric — Litres (L) to Millilitres of Oil (mL)
| Fuel (L) | Oil (mL) |
| 0.5 | 6.25 |
| 1 | 12.5 |
| 1.5 | 18.75 |
| 2 | 25 |
| 2.5 | 31.25 |
| 3 | 37.5 |
| 4 | 50 |
| 5 | 62.5 |
| 7.5 | 93.75 |
| 10 | 125 |
| 15 | 187.5 |
| 20 | 250 |
| 25 | 312.5 |
US — Gallons (gal) to Fluid Ounces of Oil (fl oz)
| Fuel (gal) | Oil (fl oz) |
| 0.5 | 0.8 |
| 1 | 1.6 |
| 1.5 | 2.4 |
| 2 | 3.2 |
| 2.5 | 4.0 |
| 3 | 4.8 |
| 4 | 6.4 |
| 5 | 8.0 |
| 7.5 | 12.0 |
| 10 | 16.0 |
| 15 | 24.0 |
| 20 | 32.0 |
| 25 | 40.0 |
Fuel Mixing Best Practices
Do
- Use high-quality two-stroke oil.
- Mix in a clean, compatible fuel container.
Shake the container well before filling the engine. - Follow the instructions on the device label.
Don’t
- Estimate oil consumption.
- Use expired or old fuel.
- Store fuel for several months.
- Use gasoline directly.
You can use a 2 stroke oil mix calculator to find most 20:1, 24:1, 40:1, 50:1 and 32:1.