Whats the difference between a 2 stroke and a 4 stroke?

What George said is right. But he was talking like a scientist or something, like when a doctor tells you what is wrong with you in medical terms that you don't understand. George gave you the right answer. I will just say a few things in lame terms so if you didn't understand what he was saying. On 2 & 4 stroke bikes, the differences are the two different types of engines. A 4 stroke engine takes twice the amount of strokes to complete a cycle than what a 2 stroke does. A cycle is what it takes for an engine to suck in fuel, make energy, and exhaust its waste. In the one engine it takes 4 strokes for the energy to suck in fuel, make energy, and exhaust its waste. The other engine sucks in fuel, makes energy, and exhaust its waste in only 2 strokes. A 4 stroke engine has a crankcase that holds oil for lubricating and it doesn't burn its oil. A 2 stroke motorcycle engine does not hold oil in the crankcase; its lubricating oil is burnt inside the cylinder, and the oil is either mixed with the gas or the engine has an oil injection system.

2 strokes are jumpier, (they want to go fast all the time). 2 strokes have more top end power than bottom end. 4 strokes have more power on the bottom end. resulting in: they are more powerful, but they dont have the jumpyness that a 2 stroke has.

2 strokes have more speed and you have to mix oil and gas for fuel. 4 strokes have more power and u just have to put gas in it.

haha jose xD four strokes are beast, had a 2 stroke 125;moved up to 250f thing runs like a dream, added a few mods and my bike is fast as ****. everyone runs a four stroke that races (not litterally) but 2 strokes are more like play bikes, you dont see james stewart, ryan dungey, chad reed racing 2 strokes ;] but anywho i have no idea the specific difference between 2 and 4 strokes just that four strokes you dont have to shift constantly.

a two stroke engine will fire every time the piston comes up a 4 stroke fires every other time it does a 2 stroke also uses a gas oil mixture where the 4 stroke burns straight gas

all these ppl are wrong 4 stroke are mostly trail riding with more torque than speed 2 stroke are racing bikes with a mean power band and a lot of torque all so 2 strokes use oil with gas 2 STROKE ALL THE WAYY