can someone tell me how an engine works?{bikes and cars}?

Answer 1

Cars and most motorcycles run on four-cycle engines. The four cycles involve movement of the pistons inside the cylinders. This is how it works:

FIRST CYCLE: Piston starts all the way up but is now moving down. A mixture of gasoline and air (usually one part gasoline to 15 parts air) is either injected into the cylinder or flows in from the carburetor.

SECOND CYCLE: Piston starts all the way down but is now moving up, compressing that mixture of gasoline and air. When the piston hits the top of its travel, the spark plug ignites the gas/air mixture.

THIRD CYCLE: Piston starts all the way up but is forced down by the explosion of the gas/air mixture.

FOURTH CYCLE: Piston starts all the way down, exhaust valves open as the piston starts moving up to force almost all of the exhaust gas out of the cylinder.

That process repeats itself over and over again in each cylinder. The cylinders are arranged in such a manner that you'll never have two cylinders doing exactly the same thing at exactly the same time. That helps regulate the power output and makes the engine run more smoothly. For example, an inline 4-cylinder engine is designed to have the two outermost pistons (1 and 4) at the top of their travel while the two innermost pistons (2 and 3)are at the bottom of their travel. So when pistons 1 and 4 are at the top of their travel, one is igniting while the other one has just finished pushing out the exhaust gas, while in cylinders 2 and 3 one has just been filled with gas/air mixture while the other one is being forced down after ignition. The ignition sequence on an inline four cylinder engine is 1-2-4-3. Can you kind of see how that works?

The ignition system for the spark plugs is electronic. It's either done by having a distributor cap and rotor, or it is done electronically with a computer controlling the ignition system. Cars and motorcycles have alternators, which are small electric generators that produce all the electricity needed for the ignition system and any other electronic devices like lights, turn signals, radios, etc. The battery is only used for starting the engine. When you turn the key, the battery provides electricity to the ignition system and to the starter, which is a powerful electric motor that actually "spins" the engine. Since the engine is precision-designed to run by itself under the right conditions, the battery shouldn't have to supply electricity to the ignition system and starter for long -- eventually the engine will "catch" and run on its own.

All the pistons, however many there are, are attached to a drive shaft. That drive shaft goes directly to the transmission, which is a complicated set of gears that are set at certain ratios. The lower gears have ratios where it may take several revolutions of the driveshaft to produce one revolution of the transmission. This gear ratio will not produce a lot of speed, but it will produce a lot of torque (which is what you need to get a heavy car or motorcycle moving from a dead stop). As the gear ratios get higher, they produce less torque but more speed.

Does that help?

Answer 2

Internal Combustion Engine - look it up on Google.
Bikes can use 2-stroke or 4-stroke

Answer 3

An engine converts the chemical energy of a fuel into mechanical energy.the basic funda is that fuel is burnt inside an engine and the energy released is converted into the rotational motion of the wheels.an engine has 4 strokes-intake,compression,power stroke and exhaust.In yhe intake stroke,fuel is taken inside the engine cylinder.in the compression stroke,the fuel is compressed .In the power strokethe fuel is burnt by producing a spark from a spark plug.Finally,in the exhaust stroke,the exhaust gases are allowed to escape from the engine cylinder.

Answer 4

you put petrol in it and hey presto

Answer 5

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Main > Auto > Under the Hood

How Car Engines Work
by Marshall Brain

Shop for Car Engines

Table of Contents




Have you ever opened the hood of your car and wondered what was going on in there? A car engine can look like a big confusing jumble of metal, tubes and wires to the uninitiated.


Photo courtesy DaimlerChrysler
2003 Jeep® Grand Cherokee Engine

You might want to know what's going on simply out of curiosity. Or perhaps you are buying a new car, and you hear things like "3.0 liter V-6" and "dual overhead cams" and "tuned port fuel injection." What does all of that mean?

If you have ever wondered about this kind of stuff, then read on -- In this article, we'll discuss the basic idea behind an engine and then go into detail about how all the pieces fit together, what can go wrong and how to increase performance.

The purpose of a gasoline car engine is to convert gasoline into motion so that your car can move. Currently the easiest way to create motion from gasoline is to burn the gasoline inside an engine. Therefore, a car engine is an internal combustion engine -- combustion takes place internally. Two things to note:

* There are different kinds of internal combustion engines. Diesel engines are one form and gas turbine engines are another. See also the articles on HEMI engines, rotary engines and two-stroke engines. Each has its own advantages and disadvantages.

* There is such a thing as an external combustion engine. A steam engine in old-fashioned trains and steam boats is the best example of an external combustion engine. The fuel (coal, wood, oil, whatever) in a steam engine burns outside the engine to create steam, and the steam creates motion inside the engine. Internal combustion is a lot more efficient (takes less fuel per mile) than external combustion, plus an internal combustion engine is a lot smaller than an equivalent external combustion engine. This explains why we don't see any cars from Ford and GM using steam engines.



Inside a typical car engine

Almost all cars today use a reciprocating internal combustion engine because this engine is:

* Relatively efficient (compared to an external combustion engine)
* Relatively inexpensive (compared to a gas turbine)
* Relatively easy to refuel (compared to an electric car)

These advantages beat any other existing technology for moving a car around.

To understand the basic idea behind how a reciprocating internal combustion engine works, it is helpful to have a good mental image of how "internal combustion" works. One good example is an old Revolutionary War cannon. You have probably seen these in movies, where the soldiers load the cannon with gun powder and a cannonball and light it. That is internal combustion, but it is hard to imagine that having anything to do with engines.

A more relevant example might be this: Say that you took a big piece of plastic sewer pipe, maybe 3 inches in diameter and 3 feet long, and you put a cap on one end of it. Then say that you sprayed a little WD-40 into the pipe, or put in a tiny drop of gasoline. Then say that you stuffed a potato down the pipe. Like this:


I am not recommending that you do this! But say you did... What we have here is a device commonly known as a potato cannon. When you introduce a spark, you can ignite the fuel.

What is interesting, and the reason we are talking about such a device, is that a potato cannon can launch a potato about 500 feet through the air! There is a huge amount of energy in a tiny drop of gasoline.

Internal Combustion
The potato cannon uses the basic principle behind any reciprocating internal combustion engine: If you put a tiny amount of high-energy fuel (like gasoline) in a small, enclosed space and ignite it, an incredible amount of energy is released in the form of expanding gas. You can use that energy to propel a potato 500 feet. In this case, the energy is translated into potato motion. You can also use it for more interesting purposes. For example, if you can create a cycle that allows you to set off explosions like this hundreds of times per minute, and if you can harness that energy in a useful way, what you have is the core of a car engine!

Almost all cars currently use what is called a four-stroke combustion cycle to convert gasoline into motion. The four-stroke approach is also known as the Otto cycle, in honor of Nikolaus Otto, who invented it in 1867. The four strokes are illustrated in Figure 1. They are:

* Intake stroke
* Compression stroke
* Combustion stroke
* Exhaust stroke



Figure 1

Understanding the Cycles



Figure 1
You can see in the figure that a device called a piston replaces the potato in the potato cannon. The piston is connected to the crankshaft by a connecting rod. As the crankshaft revolves, it has the effect of "resetting the cannon." Here's what happens as the engine goes through its cycle:

1. The piston starts at the top, the intake valve opens, and the piston moves down to let the engine take in a cylinder-full of air and gasoline. This is the intake stroke. Only the tiniest drop of gasoline needs to be mixed into the air for this to work. (Part 1 of the figure)
2. Then the piston moves back up to compress this fuel/air mixture. Compression makes the explosion more powerful. (Part 2 of the figure)
3. When the piston reaches the top of its stroke, the spark plug emits a spark to ignite the gasoline. The gasoline charge in the cylinder explodes, driving the piston down. (Part 3 of the figure)
4. Once the piston hits the bottom of its stroke, the exhaust valve opens and the exhaust leaves the cylinder to go out the tailpipe. (Part 4 of the figure)

Now the engine is ready for the next cycle, so it intakes another charge of air and gas.

Notice that the motion that comes out of an internal combustion engine is rotational, while the motion produced by a potato cannon is linear (straight line). In an engine the linear motion of the pistons is converted into rotational motion by the crankshaft. The rotational motion is nice because we plan to turn (rotate) the car's wheels with it anyway.

Now let's look at all the parts that work together to make this happen.


Related Content:

* *Explanations:
o How Diesel Engines Work
o How Rotary Engines Work
o How HEMI Engines Work
* *Expert Reviews:
o Consumer Guide Automotive Home
o New Car Search
o Used Car Search
* *Opinions:
Engine of the Future Wish List: What do you want to see in the next generation of engines?
Post your response now.




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› Introduction to How Car Engines Work
› Cylinders, Displacement and Other Engine Parts
› Valve Trains and Systems
› Producing More Power, Engine Questions
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Answer 6

maybe these links may help. (best answer)

Answer 7

it just stops