What fuel mix does a 2-stroke garden machine need? 25:1,…

Short answerAlways use the ratio printed in the machine's manual or on the fuel cap. Many 2-stroke garden machines use 25:1 with standard 2-stroke oil, while 40:1 or 50:1 is used only with high-quality, low-smoke oils approved by the maker. Mix fresh fuel in a clean can and never run straight petrol in a 2-stroke engine.

What does 25:1 actually mean?

It means 25 parts petrol to 1 part 2-stroke oil by volume. For 1 litre of petrol at 25:1 you add 40 ml of oil; at 40:1 you add 25 ml; at 50:1 you add 20 ml.

Petrol	25:1	40:1	50:1
1 L	40 ml	25 ml	20 ml
5 L	200 ml	125 ml	100 ml

Why do ratios differ between machines?

The ratio depends on the engine's tolerances and the oil the maker tested. Several of our chainsaws, for example, list 25:1 in their specifications. Using more oil than needed causes smoke and carbon; using less risks a seized piston.

How should operators mix fuel?

Use fresh petrol of the octane the manual specifies.
Pour half the petrol into a clean, marked can.
Add the full measure of 2-stroke oil.
Close and shake, then add the remaining petrol and shake again.
Use the mix within about 30 days and shake before refuelling.

What are the most common mistakes?

Running straight petrol, which ruins the piston and cylinder in minutes.
Using 4-stroke engine oil instead of 2-stroke oil.
Storing mixed fuel for months, which leads to gummed carburettors.

What should distributors do?

Print the ratio clearly on the fuel tank, include a marked mixing bottle with each machine and translate the fuel instructions into your customers' language. We can add your ratio label and mixing bottle at the factory.

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