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What's good for your bike: Carburettor or EFI?

December 29, 2013 10:47 IST

Find out the pros and cons of using and old as well as modern bike technology.

Okay, we understand that you have been into biking for some time now, and have participated in many rides. During this period, you might have come across a range of different bikes, all working on different technologies.

In your opinion, which among the carburettor and EFI technologies works better for you? I am sure, you would have an opinion and we have one too.

However, before we start deciphering the difference between the two technologies, let us have a brief introduction about them:

Carburettors

This technology has been around for over a century and is still used in numerous bikes and other automobiles. Simply put, a carburettor is a device whose job is to blend air and fuel for an internal combustion engine. It takes a decision on the amount of fuel that an engine needs, depending upon the amount of air that is pushed in, by the virtue of atmospheric pressure.

What's good for your bike: Carburettor or EFI?

December 29, 2013 10:47 IST

Electronic fuel injection

As the name suggests, EFI also does the job of carburettor but with an element of automation. In this case, the fuel is delivered from the tank to the injector through an electronic fuel pump.

Moreover, such electronic mechanism ensures that the fuel is maintained at a constant level by means of a fuel pressure regulator.

There is so much to know. Some motorcycles are still stuck to carburettor, but the advanced bikes have switched to fuel injected engines.

Debatable fact is that most of the mechanics have experience with carburettors and very few know about fuel-injection systems. Carburetted bikes are simpler to maintain and refurbish. Most people we come across are stuck with the myth that a fuel injection motorcycle increases the cost of the bike; however, most of them tend to ignore the various benefits that this technology entails.

What's good for your bike: Carburettor or EFI?

December 29, 2013 10:47 IST

Cold starts

Carburetted motorcycles are slow on cold start and they need time to speed up at low temperatures. The choke system is used to start off the cold engine. Since the fuel in a cold engine condenses and sticks to the walls of the cylinder, it is not powered easily for the engine to start. The additional fuel is supplied from the choke system to the engine.

In bikes that are fuel injected, the fuel pump is in the tank, the other important parts being an electronic engine controller and multiple sensors.

Engine type

If we debate about a computer controlled fuel delivery system, it is the fuel injected engine. The computer opens and closes the injectors, thus allowing the gasoline into the engine depending on the sensor inputs and the fuel map automatically into the computer.

The RPM, engine temperature, throttle position, manifold pressure, and crankshaft position endow with information as to the operating conditions and load on the motorcycle's engine.

A carburettor is a demand machine, dependent upon the speed of the air entering the Ventura to create the fuel-air mixture that nourishes the engine. It also preserves a series of fuel circuits to help make the most suitable fuel combination. The capacity of a carburettor to provide a good fuel-air combination is dependent upon the pace of the air going through it.

With the use of the electronic fuel injection system, the required fuel quantity for each RPM and engine load condition is located in the fuel map. Further the fuel mixture for the engine is adjusted. In some bikes the mixture is adjusted for the altering barometric pressure and altitude.

Repairing

There is another strong point to be noted while discussing the difference between Carburettor generated bikes and electronic fuel injected bikes. Carburettor problems are fixed on the side of the road with basic tools in the car's stock or by a mechanic. But in case of fuel injected systems, replacements of parts is necessary.