What is the difference between 2 and 4 stroke?

Answer 1

If I thought this was a serious question......
but i don't.



Yours: Grumpy

Answer 2

Hey, barbie, Different strokes for different folks.

A 2 stroke engine has 2 steps in a cycle. The piston draws in gas and air and it is ignited part way through the step. The power drive the piston down and when the piston reverses direction it will expel the exhaust. Then it sucks in air and gas and ignited.

A 4 stoke engine has 4 steps. Air and gas is drawn in. The mixture is then compressed, The spark ignites the mixture and piston is driven down the cylinder again. The piston then expels the exhaust.

The 2 stoke engine does not have the compression step and is less efficient.

Answer 3

Two Stroke engines have two strokes per power cycle. They are the Intake/Compression Stroke-up, (explosion) and the Power Stroke/Exhaust-down. Repeat.

Four Stroke engines have four strokes per power cycle. They are the Intake stroke-down, Compression stroke-up, (explosion) the Power Stroke-down, Exhaust Stroke-up. Repeat.

Four Stroke engines in the past have tended to operate with lower levels of oil/gas emissions in the exhaust. New designs have rendered this concept almost invalid, however.

Answer 4

In a 4-stroke engine the sequence can be written:

Compression Stroke. The piston goes up and compresses a fuel/air mixture (in a gas engine) or just air (in a diesel).
Power Stroke. The fuel is ignited (by a spark in a gas engine, by being injected into high temperature air in a diesel.) The energy released drives the piston down. This provides the momentum necessary to keep the crankshaft turning and make the other three strokes happen.
Exhaust Stroke. The piston goes up and pushes the burned gases out the exhaust valve.
Intake Stroke. The piston goes down and draws in new air, or fuel/air mixture, ready for the next compression stroke.
In a 2-stroke engine, the last three strokes are combined into one.
Compression Stroke. The piston goes up and compresses a fuel/air mixture (in a gas engine) or just air (in a diesel.)
Power Stroke. The fuel is ignited and drives the piston down. As the piston goes down it not only turns the crankshaft but also pressurizes the fuel/air mixture in the crankcase which is about to be admitted to the piston for the next cycle. Near the bottom of the stroke, an outlet opens and the exhaust gases are released. Even nearer the bottom of the stroke, an inlet opens and new fuel/air (which was just pressurized by the piston) rushes in ready for compression.
Because a 2-stroke engine gets a power stroke twice as often as a four-stroke engine, it puts out about twice as much power (and makes twice as much noise) as a four-stroke engine of the same size.

The downside is that, because the 2-stroke engine is sloppier about how it expels exhaust and takes in fuel, doing them almost at the same time, it is more polluting. Also, the 2-stroke engine lets fuel into the crankcase, where the piston can pressurize it prior to intake. In order to keep the crankcase lubricated, you have to add expensive lubricants to the fuel, and even so, 2-stroke engines don't last very long.

So 2-stroke engines are used in chainsaws and lawnmowers, where power/weight is important, but the engine isn't used for long periods so pollution and engine life are less of a concern. The continuously used engines in cars and trucks are 4-stroke engines.

Answer 5

2 Stroke Burns oil mixed with the gas...4 strokes do not. A 2 stroke engine will be able to turn more RPM than a four stroke.

Answer 6

2 inches ..??!! LOL ...hey every inch helps