Which produces more power 2 stroke or 4 stroke?
A stroke in Engine terminology is known as the process when piston moves from one side to other side of the cylinder known as TDC (Top Dead Center) and BDC (Bottom Dead Center). The basic working concept of these two types of engines is same which is, when fuel is burnt, it changes into gaseous form which increases the pressure, consequently causing force to be produced. This force is utilized in useful effort. Theoretically we can say that a 2 Stroke engine produces almost double power than a 4 Stroke Engine but its not always true. The power produced in an economical 2 stroke engine is about 1.5 times than that of an economical 4 stroke engine because some amount of fuel leaves the cylinder unburnt in two stroke engine. A short description of two stroke and four stroke engine explaining why 2 stroke produces more power than 4 stroke is given below.
2-Stroke Engine: As I have already explained what a stroke is, now its time to understand the rotation of crank and completion of a cycle with respect to stroke. In 2 stroke engine the arrangement of crank is such that when one stroke is completed it makes half of the rotation and one cycle is completed in one complete rotation of crank i.e. in two strokes. Out of these two strokes, one is power stroke (which gives power). Now ONE POWER STROKE PER ROTATION OF THE CRANK is there in 2 stroke engine for each cycle.
4-Stroke Engine: Now in this, the arrangement of the crank is such that when one stroke is completed, the crank also rotates half of the rotation but the cycle is completed in two rotations of crank. This means there are four strokes per cycle out of which, one is power stroke. Therefore ONE POWER STROKE PER TWO ROTATIONS OF THE CRANK is there in 4 stroke engine.