Do Motorcycles Have Alternators: All You Need To Know

Did you just get a brand-new motorcycle and can’t wait to take it for a spin? If you are fortunate enough to have one of the latest models, you’ll find many cool features on your motorcycle that rely on electric power.

A question starts nagging at the back of your head: how do all these components get the power supply out of this engine?

An alternator is the most commonly used component in vehicle engines that generate the current from the mechanical movement, which charges the battery.

But do motorcycles have alternators? We have got all the answers. Read on to find out!

What Is an Alternator?

An alternator is a device that produces electricity by converting rotational mechanical energy. It is also known as a synchronous generator.

Your vehicle engine produces mechanical energy from burning gasoline and diesel. This energy rotates a bar-shaped electromagnet called the rotor inside the alternator.

As the rotor spins, it creates alternating magnetic fields induced by the rotating field into the stator. The induced voltage created in the stator is then routed to other electronic components with a voltage regulator.

The alternator is the main source of electrical power for the majority of cars and motorcycles today. You can use the electricity to power your car stereo, headlights, rear lights, and anything other electrical components.

Types of Alternators


The two main alternator designs are the Salient Pole and the Smooth Cylindrical.

Salient Pole Alternator

This type of alternator is primarily found in hydraulic turbines or diesel engines, having a speed of 100 to 375 RPM. The Salient Pole Alternator features four to 60 projecting poles that are bolted to a strong magnetic wheel.

Smooth Cylindrical Alternator

A smooth cylindrical alternator is a high-speed alternator designed to rotate at 1,500 to 3,000 RPM and is compatible with two or four-pole generators.

Its rotor is made of a smooth solid, forged steel cylinder with slots machined out at regular intervals to accommodate the field coils. It has a more robust construction and noiseless operation.

Do Motorcycles Have Alternators?

Just like any other vehicle, a motorcycle’s engine also needs a power supply to run its electric components. Where does this power come from? The answer, of course, is a battery. But what charges the battery?

This is where the alternator comes in. It converts mechanical energy into electric energy to charge the battery. The alternator of a motorcycle is known as the stator. It is less intricate than alternators used in other vehicles. A stator is usually located inside a bike’s engine. Without an alternator, you’ll have a dead battery every other day.

How to Check if Your Motorcycle Has an Alternator?

There are two ways to know if your bike has an alternator. One way is to check for the presence of a belt on the engine sprocket. This belt rotates the magnet that generates the electrical current for charging the battery.

Another way to check is by reading the instruction manual that comes with your bike. As this instruction manual explains details about each part of a motorcycle, it would most likely have details about the alternator in the electric components section.

Today, you can find anything on the internet — just go and type your bike’s name and model and get all its details. This can be the smartest and easiest way to discover if your motorcycle has an alternator.

You can also get extra information about your bike’s alternator from the internet, such as its type, placement on the bike, or how to remove or install one. However, it’s not recommended to meddle with your bike’s alternator.

If you like to get into the depth of things, this video shows the working of motorcycle alternators in detail.

History of Alternators

After all the information about alternators and their types, let’s look at where it all started.

The idea of an alternator was first conceptualized in 1886 by a German inventor and engineer, Heinrich Hertz. He discovered that rotating an electro-magnet using an induced current generated a rotating magnetic field.

This discovery was the basis of what we know today as the alternator. In the late 1890s, Tesla and Westinghouse further refined Hertz’s work, which led to the invention of the first alternating current (AC) electric power transmission system.

Folsom Powerhouse carried out the first long-distance transmission of high-voltage alternating current in 1895. It transferred electricity to Sacramento using a 35 KM long transmission line with the help of newly invented AC generators.

In 1909, General Electric (GE) started using these alternating current systems in hydroelectric plants. The first AC car ignition system using an alternator was in 1911. Since then, it has been the primary power source for all motor vehicles.

Importance of Alternators


As we have discussed above, the alternator is a critical part of your vehicle’s electrical system. It allows you to run many electrical components on your bike, such as the lights, starter relay, and rectifier.

An alternator also helps charge the vehicle’s battery, as the battery provides an initial jolt to start your vehicle. When the vehicle’s battery is fully charged, it powers the electrical components of your vehicle.

It is essential to maintain the battery’s health and have it recharged regularly. If the battery is not maintained, it will lose its charge and won’t be able to start the vehicle.

In such a situation, the alternator is used to recharge the battery and provide power to the motorcycle’s electrical components.

Problems with the Alternator

The issues with motorcycles are mostly due to their electric components. You might face a situation where your bike’s battery doesn’t charge and is dead. Most likely, the reason could be a faulty alternator.

Let’s take a look at factors that lead to a faulty alternator. An alternator has a tough job as it has to generate a current all the time when the bike is running, which could heat the alternator and stop working.

In some cases, your battery might be old and the alternator has to work hard to provide sufficient current. The extra pressure on the alternator can lead to overheating.

The wiring plays an important role in all electrical components. If the wiring is not adjusted correctly, this could lead to a short circuit and ruin the alternator. So the wiring should not be compromised at any cost.

Water is the biggest enemy of electric items. If water reaches inside an alternator, it could easily ruin it.

All these are the commonly known problems with alternators. Apart from this, the problem can also be due to a manufacturing fault.

If you find that your battery is not charging even after riding your bike for a few hours, it is probably due to a faulty alternator. In such a situation, the best thing to do is to visit a mechanic who can replace it with a new one.

The mechanic will examine the faulty alternator and your bike to understand the wiring and other components that need to be repaired. If it is not repairable, you should look for a replacement.

Handling and Caring of Alternators

An alternator is a delicate machine that needs to be handled with care.

Never touch the copper wires inside, and don’t apply grease or oil to the bearings or other components inside the alternator, as the grease might get into the bearings and gunk them up. You must also not use cleaning sprays, solvents, or strong chemicals inside the alternator, as these might damage it.

To keep your alternator in good condition, give it a regular cleaning with a soft brush or a dry cloth. Depending on usage, you should also change the belts from time to time, as old belts wear out and break easily.

Apart from its smooth mechanical operation, a bike’s look also matters a lot to the owner. Detailing your bike is the best way to keep your bike in fresh shape.

Overall, the alternator is reliable and can be cleaned, recharged, and maintained easily. This video can explain four easy ways to test your bike’s alternator.

Wrapping It Up

As you can see, the alternator is an important device that converts mechanical energy into electrical energy. You can use this electricity to power your bike and charge the bike’s battery.

The alternator is a critical part of the electrical system in your motorcycle. It is important to clean, maintain, and replace the alternator as needed to ensure that your bike’s electrical system is working correctly.

Do motorcycles have alternators? Yes, nearly all bikes come equipped with an alternator. Keep it clean and properly maintained to enjoy a fully functional engine.

Don’t Stop Here

More To Explore

how to flush engine block

How To Flush Engine Block on a Motorcycle?

You might be surprised to know that you must flush your motorcycle’s engine. You are not alone, as most people often ignore their vehicle’s engine

Join our newsletter & get latest bike update