If an engine can go for 10000 rpm’s before it wears out; a 4 stroke engine with 100 rpm will run for 100 minutes than the other 2 stroke engine which has a higher rpm of 500 & will run for only 20 minutes.
No extra addition of oil :- Only the moving parts need lubrication intermediately. No extra oil or lubricant is added to fuel.
DISADVANTAGES OF 4 STROKE ENGINE :-
- Complicated design :- A 4 stroke engine has complex valve mechanisms operated & controlled by gears & chain. Also there are many parts to worry about which makes it harder to troubleshoot.
- Less powerful :- As power gets delivered once every 2 rotations of crankshaft(4 strokes), hence 4 stroke is less powerful.
- Expensive :- A four stroke engine has much more parts than 2 stroke engine. So they often require repairs which leads to greater expense.
ADVANTAGES OF 2 STROKE ENGINE :-
- Simple design & construction :- It doesn’t have valves. It simply has inlet & outlet ports which makes it simpler.
- More powerful :- In 2 stroke engine, every alternate stroke is power stroke unlike 4 stroked one in which power gets delivered once every 4 strokes. This gives a significant power boost. Also, the acceleration will be higher & power delivery will be uniform due to same reason.
- Position doesn’t matter :- 2 stroke engine can work in any position as lubrication is done through the means of fuel (as the fuel passes by through whole cylinder & crankcase).
DISADVANTAGES OF 2 STROKE ENGINE :-
- Less fuel efficiency :- For every alternate power stroke, fuel gets consumed every alternate stroke. This makes the engine less fuel efficient although it results in uniform power delivery.
- Oil addition could be expensive :- Two-stroke engines require a mix of oil in with the air-fuel mixture to lubricate the crankshaft, connecting rod and cylinder walls. These oils may empty your pockets.
- More pollution :- 2 stroke engine produces a lot of pollution. The combustion of oil added in the mixture creates a lot of smoke which leads to air pollution.
- Wastage of fuel :- Sometimes the fresh charge which is going to undergo combustion gets out along with the exhaust gases. This leads to wastage of fuel & also power delivery of the engine gets effected.
- Improper combustion :- The exhaust gases often get trapped inside the combustion chamber. This makes the fresh charge impure. Therefore maximum power doesn’t get delivered because of improper incomplete combustion.
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