How were the 2-cycle premix fuel run in a 4-cycle engine options tested?

Each option was put through: running a 4-cycle engine on a 40:1 gas to 2-cycle oil premix; running the same engine on an intentionally much richer 4:1 gas to 2-cycle oil premix; visual smoke/combustion observation and spark plug inspection; compression test (PSI) before versus after running on 2-cycle oil premix, per chapter markers; engine and exhaust temperature check, per chapter markers.

Where can I watch the full test?

The complete hands-on test video is on the original creator's channel: https://www.youtube.com/watch?v=QLW5KEslF3A

Myth test1 productsMyths & Experiments

2-cycle Premix Fuel Run In A 4-cycle Engine: The Test Results

A head-to-head test of 1 2-cycle premix fuel run in a 4-cycle engine options with the measured results for each. See how they ranked and watch the full test video.

The verdict

Ranked first

2-cycle oil premix (generic, no brand named)

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The measured results

Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.

Product	40:1 premix test	4:1 extreme premix test	Smoke/combustion	Spark plug condition	Compression	Engine/exhaust temperature
12-cycle oil premix (generic, no brand named)	mixed 20 oz of 87 octane fuel with a half ounce of 2-cycle oil; ran the small 4-cycle engine on this premix	mixed 16 oz of fuel with 4 oz of 2-cycle oil for an intentionally much richer ratio to see how the engine handled it and how much carbon buildup would occur	narrator expected a lot of smoke and wore a respirator in anticipation, especially with the 4:1 ratio, but the engine produced far less smoke than expected; attributes this to modern 2-cycle oils burning off well inside the combustion chamber	looked pretty clean after running on the premix	per the video's chapter markers, compression measured 100 PSI before introducing 2-cycle oil and 105 PSI afterward, a slight increase rather than a decrease	per the video's chapter markers, described as normal

How it was tested

running a 4-cycle engine on a 40:1 gas to 2-cycle oil premix
running the same engine on an intentionally much richer 4:1 gas to 2-cycle oil premix
visual smoke/combustion observation and spark plug inspection
compression test (PSI) before versus after running on 2-cycle oil premix, per chapter markers
engine and exhaust temperature check, per chapter markers

“I'm really impressed with how well this engine ran on the premix. I really thought I'd see a lot more smoke, especially with the four to one gas to oil ratio.”
From the test video verdict.

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