No vehicle would start without electricity, and the same goes for motorcycles. Electricity is required even in single-cylinder dirt bikes to create enough power to produce a spark for it to start. On the other side, there are bigger motorcycles equipped with heated grips, stereos, or GPS, which leads to a bigger need for a power supply.
So how to fix a motorcycle alternator? Remove the alternator off the motorcycle. Drain the oil and detach the wiring. After doing that, separate the stator from the alternator. Take a new stator and reinstall it. Replace the flywheel rotor and assemble the alternator. Pour new oil and return the alternator to the motorcycle.
Further in this article, we will teach you about the alternator basics, such as what the alternator is, maintaining it, and the differences between alternator and stator.
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How to Fix a Motorcycle Alternator?
A motorcycle alternator is sometimes called a stator or a generator, and it is an internal unit of a motorcycle’s power system. Its primary purpose is to create a sufficient amount of electrical power used for recharging the motorcycle’s battery. If the alternator gets malfunctioned, the motorcycle’s lighting and starting systems will rely only on the battery, and the battery is not capable of dealing with this much overload (pressure) for a longer period of time.
The steps for replacing the alternator can be used on most motorcycles, although the alternator can be positioned on different motorcycle spots depending on each model.
Tip: Use a factory service manual to know the correct specifics of your bike.
These are the steps that you need to follow to repair your alternator:
Step 1: Remove the Motorcycle Cover
Most often, the alternator is positioned on the left side of the motorcycle.
Note: There are touring and cruiser models with alternators built on the right side, so have that in mind if you own this type of motorcycle.
Remove the alternator cover from your motorcycle. If you need more space to reach the motorcycle’s alternator cover, you will also have to take off any exhaust components or other motorcycle parts.
Step 2: Drain the Oil
Take a drain pan and put it under the motorcycle. Use a socket wrench and take off the oil drain plug. Make sure that all the oil is completely drained and return the drain plug. Take the drain pan and place it under the alternator cover.
Step 3: Detach the Wiring
Detach the alternator’s wiring harness out of the motorcycle’s wiring harness. Take a socket wrench and use it to take off the screws on the perimeter of the alternator cover. Take the cover off and leave the drain pan under the alternator cover that any remaining oil drains to the pan. Take off the alternator covers gasket and throw it away.
Step 4: Remove the Stator
Turn over the alternator cover. Take off the screws that hold the alternator’s magnetic stator together with the alternator cover using an Allen key or Torx (depending on your motorcycle type). Remove the stator out of the cover. Put a new stator into the cover. Use an Allen key or Torx to tighten the screws of the cover. Get a new gasket and put it on the alternator cover.
Note: Allen key and Torx may look the same, but they are very different.
Step 5: Remove the Flywheel Rotor
Detach the flywheel rotor from the crankshaft with a socket wrench. You need to take off the flywheel rotor mounting screw to do that. Use a socket wrench to tighten the mounting screw. Once you have done that, take a new flywheel rotor and install it on the crankshaft.
Step 6: Assemble the Alternator
Put the alternator cover back to the flywheel rotor and return it to the motorcycle. Gently tighten the alternator cover’s screws to their place using an Allen key or Torx. Make sure that all the screws are tightened lightly to the cover of the alternator. Use a criss-cross pattern to tighten the screws completely. Connect the alternator back to the motorcycle’s wiring harness.
Step 7: Pour Fresh Oil
Take off the motor’s oil filler cap and pour fresh oil into the oil filler. After doing so, return the oil filler cap. Clean any oil traces that might happen while you are pouring the oil.
Step 8: Return the Parts
Return all the components you previously took off ( while completing Step 1).
Motorcycle Alternators and Stators: The Basics
An alternator is a device installed on vehicles that is responsible for the vehicle’s power supply. What it does is shift motion energy into electrical power. An alternator is an all-in-one device that creates and delivers electrical power to the vehicles.
Although the word alternator mostly refers to automobile components, the alternator is defined as a gadget that uses mechanical motion to create alternating current (AC).
Motorcycles produce electricity just like cars do, but there are some differences between these two types of vehicles and the way they generate power. A stator is one part of the electrical system responsible for creating current for motorcycles. A stator is not integrated as an external section; instead, it is placed inside the engine.
Note: Stators wires are placed throughout the engine case and lead all to an external rectifier (regulator) which is responsible for transferring alternating current (AC) into direct current (DC).
The rectifier (regulator) has one more important task to do, and that is maintaining the optimal level of electricity since a higher level of current than the proper one can lead to dangerous situations such as overcharging the battery. The stator produces a higher amount of power as you ride faster and the engine speed increases, and if this is unregulated can lead to some damage.
What Is a Motorcycle Alternator?
A motorcycle alternator is a gadget whose purpose is to use the engine’s mechanical motion and produce electrical power. Three main things are needed to produce electricity:
- motion
- a coil of wire
- a magnet.
An engine rotation creates the motion, producing electrical power along with the magnet and coil of wire.
Note: Motorcycles require direct current (DC) to supply the electrical system.
The rectifier (regulator) is required for completing the system because motorcycle alternators create alternating current (AC).
Do Motorcycles Have Alternators?
Motorcycles have alternators, although there are not so many external all-in-one alternators. The creation of electricity is handled by a rectifier(regulator) and stator.
Stator vs. Alternator: What is the Difference?
The difference between stator and alternator is the magnet type since the alternator uses an electromagnet while the stator uses a permanent magnet. While the motorcycle stator is one of the electrical system components, a motorcycle alternator is a set of all the parts in which the stator is involved, along with a rectifier (regulator) and magnets.
The first thing that we need to do when we try to compare these two and notice the difference is to determine what exactly we are comparing and the specifics of both of these components.
The electrical system consists of a motorcycle stator, one of the electrical system’s components that create AC current when combined with a rotating magnet. Stators are located within the engine case.
On the other hand, an alternator is an externally placed component that is fully self-contained and produces DC current.
Note: A rectifier (regulator) is an electrical gadget that turns alternating current (AC) into direct current (DC).
If you want to know more about stators, click on this link leading you to the article about How to Fix a Motorcycle Stator, How to Recognize Signs of a Bad Motorcycle Stator, and How to Increase Its Lifespan.
How to Test a Motorcycle Alternator?
Most of the riders think about a dead battery when they face a starting issue. This can be the correct assumption most of the time since motorcycle batteries tend to fail more often than the alternators do. However, before you conclude that the battery is dead and faulty and get a new one, try to get expert advice from an experienced technician since he can tell you if there is some type of charging problem or something else responsible for the issue.
Replacing a battery won’t fix the problem if there is some kind of motorcycle charging system issue. Also, you will have to charge the battery fully before testing it static or load.
A technician has a multimeter to run a test on a motorcycle alternator. He can test the alternator either on a running or non-running engine. When the engine is not running, a technician runs a test to see if there are any broken winding wires, while when the engine is up and running, a technician runs a test to see how much voltage is going in the battery.
There are a couple of tests and chronological steps that help a technician to determine if there are any issues in the charging system and to conclude if the battery is responsible for the engine not being able to start.
Here is a great video about changing an alternator cover:
Conclusion
A motorcycle alternator is responsible for charging your bike and providing enough electrical power. It is very important to know how to deal with the issues that can happen to your alternator. This article was written as a guide that will show you how to fix a motorcycle alternator, test it, and the differences between an alternator and a stator.
We hope you liked this article and learned a lot of new and helpful information.