Like cars, motorcycles are produced for quite long period of time. Nowadays there are many moto-brands on the market. Each of them has its own history.
Note that two-stroke engine, as its four-stroke competitor, has been used for more than a century. Engine production has been interfered neither by wars, nor by crisis. On the contrary, wars were force for progress, as showed 20-th century. For long history of motorcycles many people highly appraised the work of two-stroke engines. This article deals with this type of power pack, practical use of which goes back to far 1800-s.
In 1807 French inventor François Isaac de Rivaz constructed first combustion engine. Its operation principle based on active powder firing. Two-stroke engine was constructed a bit later, in 1878 by Dugald Clerk.
Two-stroke engine looked a bit differently from the one used nowadays. This invention brought many advantages in human life. But there are few disadvantages of this power pack. It consumes much more oil, than four-stroke engine. Anything else will be described below.
Description of two-stroke combustion engine
Engine mentioned above was constructed almost in the same time as four-stroke one, which was assembled by Nicolaus August Otto. Two-stroke petrol engine became a regular fixture much later after that.
Today, there are many modifications for all types of engines. For example, there are many varieties of ignition for two-stroke engines. Most often current moto-manufacturers use breakerless ignition system. The construction scheme of 2-stroke engine can also be different. All brands build it with due account for modern market tendencies and their historical traditions.
Two-stroke engine has many differences with four-stroke analogue. First, working cycle of this power pack is fully performed for one crankshaft rotation.
Second, even 2-stroke diesel engines limit their processes by compression and extension. Instead of intake and exhaust periods as in 4-stroke engine, 2-stroke has cylinder drain. It is performed in the moment, when piston position is near lower dead center. And entering gas pushes out cylinder exhaust gases.
Differences between 2-stroke and 4-stroke engines
Two-stroke engine has many advantages. The most important ones are caused by its peculiarities, working principle of which is considered most simple, but very oil and fuel consuming.
2-stroke petrol engine is not just different in working cycle performance. It has really enormous power, created per one volumetric unit, in comparison to 4-stroke engine. Either way, implemented scheme of 2-stroke engine reduces its efficiency.
Two-stroke engines are used for compactness. Small vehicles are usually equipped with them, for example, motorcycles. There is no point in installing it into a car.
Oil in 2-stroke engines is more like disadvantage. The principle of such engine is just to “throw” it in emission.
Besides, these are not saving engines, despite of all its theoretical pros, in practice, they lose plenty of power. In other words, 2-stroke engine with cylinder volume as of 4-stroke is more powerful in theory, but in practice it is never possible to implement this advantage.
The interference for this perfection is insufficient cylinder drain in comparison to normal intake and exhaust.Still, 2-stroke engine is 1.5 more powerful, than 4-stroke.
Advantages of two-stroke engine
The main advantage of this engine is absence of bulky valve system and camshaft. Its construction has no bulky systems providing greasing and gas distribution. It concerns only petrol engines.
There are other pros. For example, it is much easier to produce two-stroke engine, which makes its cost lower.
Besides, its operational principle is very simple, so, there are no complications with refueling. Ignition of 2-stroke engine is as effective, as of 4-stroke.
Two-stroke combustion engine is an important achievement of humanity on the way to sci-tech perfection. With all its advantages and disadvantages, bikes equipped with 2-stroke engine are capable to serve as long as the ones with 4-stroke engine.
So, 2-stroke engines of motorcycles, as well as of cars, slowly fall into oblivion. Factories, which once produced these engines, restructured for manufacturing another production. Those, which have not been repurposed – just stand idle.