Motorcycle Carburetor Vs Fuel Injection: What Are The Key Differences?

Are you thinking of buying a motorcycle? Whether new or old, one thing you must decide is if you want one that uses a carburetor or fuel-injected system. After all, each of these fuel-feeding systems has its own pros and cons. 

This, therefore, leads us to the question, which is better between these two fuel feeding systems, and what are their differences, if any? 

The truth is, it all depends on your preferences because, for instance, a carbureted engine in a motorcycle is easy to repair compared to a fuel-injected engine. On the other hand, you will find that bikes that use a fuel injector offer better performance and fuel efficiency. 

In this guide, we’ll delve deeper into fuel injected vs carburetor differences, what they are, plus how they work, so you have an easy time deciding which is the best option for you. 

What Is Carbureted Engine In A Motorcycle?

In simple terms, a carbureted engine is a simple and low-cost mechanical fuel feeding system that works by mixing air and fuel. The mixture is then delivered to the engine of your bike to power it. 

Compared to other fuel-feeding systems, a carbureted engine is an older mechanism. But over the years, these systems have been improved to ensure better performance.  

What Is Carbureted Engine In A Motorcycle

However, what stands out about carburetors is the fact that they are inexpensive, easy to repair and replace, plus they are generally durable. Even better, a carb is built separately from your motorcycle engine. Therefore, you can easily remove it for servicing or replacement without interfering with the engine. 

What is fuel injector in a motorcycle?

This is a fuel-feeding device comprising various electronic parts and sensors. As such, the device is controlled by an Electronic Control Unit (ECU) that determines the amount of fuel and air to be supplied to your bike’s engine. Consequently, you get to enjoy better fuel efficiency and mileage. 

However, unlike a carbureted engine, air and fuel only mix once they get into the engine of your bike to ensure more efficient combustion. 

What is fuel injector in a motorcycle

And just like carburetors, fuel injectors (FI) for motorcycles have also been around for quite a while now. But because of their high fuel efficiency and performance, you will find that most bike manufacturers prefer them over carbureted engines. 

How does a carburetor work in a motorcycle?

Essentially, this device works by mixing fuel and air and then feeds the mixture to the engine or simply the combustion chamber. But how is it able to achieve this? Well, the carburetor features a component called the main jet that draws air into your bike’s engine. 

The main jet also has a jet needle that allows even more airflow into the carb. This usually happens when you’re riding your motorcycle at high throttle speeds. On the other hand, the carburetor features a slide valve and pilot jet. These two systems help regulate airflow when you are cruising at lower speeds.

How does a carburetor work in a motorcycle

In addition, the carb has a float bowl where it stores the fuel. So, once you open up the throttle of your bike and more air enters the carburetor, air tends to suck in the fuel from the bowl. The mixture is then delivered to the engine of your motorcycle. 

How does a fuel injector work on a motorcycle?

A fuel injector works by measuring the amount of air going into the engine of your motorcycle using an Electronic Control Unit (ECU). It then supplies the fuel needed by the massive air. 

Besides the ECU, the fuel injector on a motorcycle also features several electronic sensors. These are built to tell the computer exactly what the engine of your motorcycle is doing. The computer then determines how much fuel is needed to optimize your bike’s performance. 

For instance, when the engine of your bike is warming up, the sensors will communicate to the ECU and tell it to reduce the air and fuel mixture since you will need less fuel to power up your bike. 

How does a fuel injector work on a motorcycle

On the other hand, if the engine of your motorcycle is very cold, the temperature sensor will tell the ECU to increase the air/fuel mixture that is enough to fire up the engine. 

Carburetor vs. fuel injector

You probably are wondering, which is better between carb vs fuel injection? Let’s look at some of their key differences. 

Carburetor vs. fuel injector

Performance: Is a carburetor better than a fuel injection?

The answer is no. A carburetor is not really better in terms of performance when compared to fuel injection systems. This is because carbureted engines are designed to determine fuel and air quantity based on the throttle speed you apply on your bike. Simply put, everything is done mechanically.

An FI system, on the other hand, is electronically controlled, thereby ensuring a precise air-fuel mixture. So, unlike it is with a carb, you don’t have to worry about changes in fuel temperature and air pressure. Consequently, this ensures better engine performance. 

Problems: Which is more prone to problems and why?

a carburetor

Overall, a carbureted engine is more susceptible to problems compared to a fuel injection system for many reasons. For instance, you will find that its diaphragm components are not sturdy enough and hence can be damaged easily. 

On top of that, because the carburetor operates mechanically, it means that you sometimes have to deal with an incorrect air-fuel mixture ratio. And as a result, you may experience sluggish acceleration, poor fuel economy, and backfiring or misfiring with your motorcycle. 

Which gives more mileage and why?

A FI system offers better mileage. This is because it is able to accurately measure what exactly air-fuel mixture that the engine of your bike needs using its electronic sensors. This results in better fuel economy and mileage.

With carburetors, you have to tune them if you want more mileage or power, but the process is automatic for fuel-injected engines.

Which one is less harmful for the environment?

a carburetor

It’s definitely the fuel injector. This is because it uses an Electronic Control Unit designed to ensure your bike’s engine receives the precise air-fuel mixture.

So, unlike a carburetor, the injector will constantly change the air-fuel mixture to optimal levels based on factors such as riding parameters, engine temperature, and engine speed. Consequently, this helps ensure cleaner combustion, thereby leading to low emissions of harmful gasses like carbon monoxide. 

What about cold start?

Unfortunately, in cold temperatures, carbureted engines usually have a hard time vaporizing all the fuel in the engine because it is usually stuck on the walls of the cylinder. 

As such, you will find that the engine tends to not get an adequate air-fuel mixture, thereby making it hard to start. So, at low temperatures, you must give your carbureted motorcycle some time for the engine to warm up before hitting the road.

What about cold start

Cold starts on fuel-injected engines are relatively easy. You just turn the key, press the start button, and you can hit the road immediately. 

Throttle response

A carbureted engine features a throttle plate that regulates the amount of air-fuel mixture delivered to the engine of your motorcycle. Unfortunately, because the whole process is mechanical, there is usually a certain degree of lag from the throttle body. As a result, this tends to cause a slow throttle response.

With fuel injection motorcycle engines, they boast a better and quicker throttle response. This is because the fuel supply is controlled via electronic sensors that make complex calculations to ensure only the right amount of fuel-air mixture is delivered to the engine. 

Versatility

Overall, fuel injectors seem to be more versatile than carburetors, which explains why we have many motorcycles using fuel-injected engines. But what makes them highly versatile? Well, it is because they are less prone to damages, have faster throttle response, offer better fuel efficiency, and have cleaner combustion. 

Carburetors, on the other hand, don’t provide better fuel efficiency and are more prone to both wear and tear. Therefore, you might not find them as versatile as fuel injectors. 

Why are we seeing more and more fuel injector motorcycles?

One of the main reasons is because, with fuel injectors, it is possible to precisely control the amount of air-fuel mixture that is delivered to the engine, which is not the case with carbureted motorcycles. As a result, this ensures that your bike uses fuel most efficiently and reduces carbon mono-oxide emissions. 

fuel injector motorcycles

Additionally, the costs of maintaining a carbureted engine are relatively high compared to a fuel injector bike. This is because the pilot jet of the carburetor has a tendency of clogging up quite often. But with fuel injectors, rarely do they break down unless the ECU fails. 

Can you convert a carburetor to fuel injection on a motorcycle?

Yes, it is possible. You just need to buy a fuel injection conversion kit which you can easily find in most motorcycle accessory outlets. Using the kit, you can remove the carb and replace it with a fuel-efficient injector. 

The kit basically comprises an ECU, various sensors, a fuel pump, a fuel line, and a throttle cable. However, you must find one that is compatible with your motorcycle. 

Do carburetors make more power?

Interestingly they do, but only if the carburetor is correctly tuned. However, since it is easier to tune a fuel injector using the electronic control unit, fuel injectors are considered to make more power. 

However, a carburetor might make more power depending on the manifold. For instance, a carb with a high-rise manifold might provide you with more horsepower and power than one with a low-rise manifold.  

Conclusion

Overall, fuel injection systems in motorcycles seem to have the upper hand in so many aspects compared to their carbureted counterparts. Not only are they fuel-efficient and cleaner for the environment, but they also boast a faster throttle response. Their main drawback is that you may find them a little pricey. However, if you’ve got a flexible budget, then you will find them an excellent choice. 

On the other hand, carburetors are also good, especially if you’re looking for a less expensive system that you can easily repair or replace by yourself. The best part is that you can easily tune your carbureted engine motorcycle based on whether you want more mileage or power.

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