Motorcycle Carburetors.

6:47 PM 4/27/2021

Motorcycle carburetor plays an important role and it takes a big role in the running of the motorbikes, Scooters and other petrol vehicles. When you buy a brand new motorbike, the carburetor comes as a fine tuned one to provide you with the best performance. Fine tuning Motorbike carburetor will provide you smooth running, quick acceleration and fuel efficiency. If your motorcycle is with 4 numbers of cylinders then it will have 4 numbers of carburetors in parallel.

Latest large and medium sized engine fitted motorcycles are now coming with Fuel Injection (FI) system that is supported by many electronic sensors. In the USA, EU and India the governments are asking the motorcycle manufacturers to be with 0% carbon emission from the engines. Nearly all the new and above 125cc motorcycles are fitted with the latest fuel injection system. As per India regulation all the motorcycles above 125cc must be fitted with Fuel Injection (FI) to meet the BS-IV (From April 2019) emission standard. So after some years the carburetor will be fitted only to the small motorcycles only. That is too economical reason as the Fuel Injection unit is expensive one that consists of sensors and computer technology to operate it and repairing and maintenance of it will too cost a lot..

Motorcycle carburetor.

Motorbike carburetor

The carburetor gets petrol from the fuel tank by the gravity force. The nozzle (Needle) assembly in side of the carburetor vaporizes the petrol for to fire in the engine chamber. It got mixed with the incoming air and makes it as air mixed petrol vapor that comes to fill the vacuum created by the piston in the cylinder. So the rich mixture passes in to the cylinder to be fired by the spark plugs electric ignition to provide the power for operation. The carburetor consists of many parts where some are preciously made such as the jet Nozzle.

In the older model carburetor there are air screw and petrol vapor screws. Now the latest motorbikes and scooters are coming with a single screw to adjust the air fuel mixture. After good warm up you can adjust this screw to get the better idle speed. It is better to do the job by your mechanic. If you used to ride motorbike in the night time, then ask the mechanic to switch on the head light and to adjust to get the idle speed.

There is a choke fitted in for cold start which will reduce the air flow and make the air fuel mixture richer with petrol for easy starting.


My Motorcycle Engine revolution is going high, when I start it in the morning?

Latest motorcycles are fitted with auto choke system. In the morning start, the Auto Choke will raise the engine speed to get it warm. Once the engine becomes with normal temperature the auto choke will cut and the motorcycle or scooter engine will come to normal idle speed. Some motorbikes have indicator that will display cold engine notice. In the other models you have mechanical choke and can be operted when it is needed.

When I stop the motorcycle, I see petrol running from the carburetor. What to do to prevent it?

As a temporary solution, close the fuel petcoke once you stopped the engine. The carburetor’s jet needle is damaged. So it allows the petrol to be in excess in the chamber and to over flow. This Needle jet set should be replaced by your mechanic.

While riding at normal speed, the motorbike suddenly slows down. What may be the reason?

First open the drain screw of your carburetor, if water is coming through it means that was the problem. If you found water in the drain, do this procedure at least twice after some interval. The tank too should be cleaned, if there is any water. This should solve your problem. Otherwise go to your garage and consult with them.


How Does A Motorcycle Carburetor Work?
Motorcycle Carburetor Cleaning
Carburetor adjustment and its importance in bike engine performance.

Super Motorcycles

You can read about the motorcycles that are called as popular, super, top 10 and dream motorcycles in the riders' world. It can be a cross country machine, cruise, speed star, highway rider or GP model. Read More

Motorcycle Shows

Here you can find the local and International motorcycle show and motorcycle related events information. These shows make links between Motorcycle enthusiasts, manufactures, dealers and media people. Read More

Top Selling Motorcycles

Top Selling Motorcycles in Asia region are here. This list didn't count on the Indian made machines although India got many special bikes. We will look at them in another sector.