Two-stroke (or 2-cycle) engines require a mixture of fuel and oil be added to the fuel tank. This mixture results in both engine combustion and lubrication. Operating a 2-Stroke engine on gasoline alone will result in engine failure.

What happens if you don't put oil in a 2-stroke?

But running a two-cycle engine with too little oil can actually destroy the unit. Oil helps cool the piston and cylinder by keeping them evenly lubricated. Without lubrication, the metals can melt and potentially grate against each other, transferring metal to and from one another and permanently distorting them.

How does a 2-cycle engine get lubricated?

Lubrication. Two-stroke engines use their crankcase to pressurize the air-fuel mixture before transfer to the cylinder. Unlike four-stroke engines, they cannot be lubricated by oil contained in the crankcase and sump: lubricating oil would be swept up and burnt with the fuel.