5 Common Bad Stator Symptoms Harley Davidson – Motorcycle Health

What are the real symptoms of a bad stator on a Harley? It’s really hard to tell because most of the symptoms of this component can also be symptoms of other components.

Fortunately, however, we have the experience of other riders on the Internet, who have faced these problems and who have managed to solve them.

In this article, you will first find out what the stator does. After that, we will go over the most common symptoms of bad stators and, last but not least, some solutions to these problems, if there are any.

So without further ado, let’s talk about stators!

What Is The Stator And How Does It Work?

What Is The Stator

First of all, what is the stator supposed to do in the first place? Before everything else, we need to understand how it should work normally. The role of the stator is that of powering all the electronic components of the motorcycle as a whole.

Of course, this also includes the particularly important function of powering the spark plugs, so as to create sparks. In fact, most symptoms of bad stators are related to this function. Most often, a bad stator will make it difficult for the spark plugs to do their job properly.

The spark plugs will work worse and worse and eventually they won’t be able to make any sparks, meaning you won’t be able to start the motorcycle at all. And since this is the case, then we should understand why the stator is a very important component: it is one of those components that ensure the start and operation of the motorcycle, especially the engine.

Sure, bad shocks or deficient clutches are serious issues that greatly decrease the ride experience, but a bad stator can make your bike unable to carry out its most basic functions.

Most Common Bad Stator Symptoms Harley

As we explained in the introduction, the reason why a symptom of bad stators is difficult to identify is that most of them may be symptoms of other components. For example, it would be very easy to believe that there is a stator problem, when – in reality, the problem is actually with the spark plugs, or maybe the battery.

The opposite also stands. In fact, people often check the stator last, only after suspecting the battery and the spark plugs.

1. Motorcycle is hard to start/doesn’t start at all

This is the simplest symptom. As explained above, the stator is responsible for powering the electronic components, including the spark plugs. So, when you try to start the bike, it may be very difficult or impossible. This could be because of a faulty spark plug, but also because of a failing stator that needs to be taken care of.

2. Misfiring 

When you ride the motorcycle and the engine has a misfire, it should feel as if the bike loses a bit of its power. It feels like hesitation and, just like in the case of the previous point, it could get to the point where the bike stops working completely because there is no spark to keep the engine going.

From a technical point of view, misfiring refers to desynchronization in the process of burning fuel. If obviously, the occurrence of misfires is a symptom of bad stators and, what’s more, they usually lead to backfires.

3. Backfiring


Backfires and misfires usually go hand in hand. If the stator doesn’t generate the spark when it should, the ignition can happen all the way into the exhaust system. In other words, the unburnt fuel is ignited in the exhaust pipe, which can even damage the exhaust and other components of the bike.

It can be scary, especially the first time, because you get the impression that the bike is not working as it should. And it doesn’t! But nothing terrible will happen in the short term. Next up we have 2 symptoms that could help you identify more easily than the first three.

4. Low and high RPMs discrepancies

Here it gets easier to tell whether the problems are actually caused by a bad stator or not. It happens in the case of bad stators that the bike works perfectly at lower speeds, so also at lower RPMs.

The misfires and backfires start to happen at higher RPMs. This is caused by a bad high-speed coil. And yes, the low-speed coil can also go bad, resulting in ignition problems when you’re riding at low speeds, although the bike seems to run flawlessly at high speeds.

5. Low and high-temperature discrepancies

Here is another sign that your stator could be bad. There may be discrepancies at different temperatures, not just at different RPMs. In other words, your engine could misfire and backfire at higher or lower temperatures.

So this is something to keep an eye out for: under what conditions does your bike start behaving other than it’s supposed to? Answering this question could greatly help you identify the failing component.

The Solutions to Harley Davidson Stator Problems

So far we have talked about the symptoms of bad stators, but is there a solution to these? Or rather, can you fix a stator in your own garage? Our answer is yes, but you might want to consider some other options as well.

You see, the stator is a very important component on any bike, and if you don’t take care of it, you might regret it later. But people tend to avoid working with wires and other electronic components because they are usually much more dangerous and much more complicated to deal with.

Repairing a bad stator is very tiresome and it can also be more expensive than buying a new stator. What’s worse is that there are rather few places that are down to rewind and repair a stator, with people complaining about the internet that companies are only willing to rewind good stators for higher power output.

The only viable solution, and the one we recommend, is to buy a new stator, although even this has a set of drawbacks. If you have a relatively old bike model, you might notice that stators are more expensive. It’s a shame because old bikes are particularly those that tend to have failing stators.

But, overall, it is the only solution we can recommend. This way you can be sure that the new stator will be good for a long time and that you will not encounter any problems rewinding it by yourself.

How To Test The Stator Of A Harley Davidson?

If you want to be even safer, and if you feel that the symptoms listed above are not specific enough, there is another way to test the stator of a Harley Davidson. But, because the process can be explained better and easier in the form of a video rather than in the form of text paragraphs, here you can find a video tutorial that will definitely help you a lot.

Using this technique is arguably better because it allows you to accurately identify the true origin of the problems you’re dealing with. As you already know, the symptoms discussed earlier may not be exclusive to stators.

But with a voltmeter, you can finally find out whether the stator is faulty or if there’s something else that needs to be checked. You can also find an additional video at the end of this article.

Preventing Stator Issues

It’s always better to prevent a problem than to try to solve it, isn’t it? Taking good care of your bike will greatly enhance the life expectancy of your bike as a whole and, implicitly, of your stator.

But what can you really do in order to prevent your stator from going bad? After all, all the elements of a motorcycle will break down over time, there’s no doubt on that one.

1. Mileage

Mileage is the number one killer because, the more you ride, the more your stator will be exposed to wind, dirt, heat, and other external objects. So do yourself a favor and keep everything clean.

If you do this occasionally and you manage to keep your bike clean, your stator could work perfectly even for hundreds of thousands of miles! However, there are two other things that you should take into consideration.

2. Amperage

We were saying earlier that it’s a good idea to understand what a stator does. And we have established that this component is responsible for powering all the electronics that you have on the bike.

But the stator has certain limits and, the more accessories we have on the bike, the harder it will be for the stator to cope and provide power for everything. Obviously, the ignition is the basic function to which the stator contributes, so we cannot avoid it. But we can avoid crowding the motorcycle with electronics.

The more we have, the higher the amperage, meaning the stator has to work harder. This is very likely to kill your stator eventually.

3. Vibration

This is another thing that you could avoid. Specifically, you need to avoid potholes not only because they are uncomfortable, but also because they take a toll on your bike, including on your stator. This is another reason to invest in a good pair of shock absorbers.

Frequently Asked Questions About Bad Stator Symptoms

FAQ Bad Stator Symptoms Harley Davidson

Q1: How do I know if my stator is bad on my Harley?

A: There are a number of symptoms for bad Harley stators. First of all, it may be difficult for you to start the bike.

While riding, you might experience misfiring or backfiring, which – again – are common symptoms for failing stators.

Additionally, the intensity of these symptoms may vary with temperature and RPMs.

Q2: What causes the stator to go bad on a Harley?

A: The causes are not as complex as identifying the symptoms. Sometimes, the causes can be of external origin, and here we refer to dirt, wind, water, and so on.

But more important than these are vibrations and high amperage, especially the latter.

High amperage means having many electronic accessories connected to your bike, accessories that need to be powered by – you guessed it – the stator.

By vibrations, we refer especially to potholes and obstacles on the road. Each strong blow affects the stator.

Q3: Will a bad stator kill a regulator/battery?

A: A bad stator is not only going to make it impossible for you to start the bike, but it’s also possible to make other components stop working.

Yes, it’s entirely possible for a stator to kill the regulator and even the battery, giving you another reason to replace it ASAP.

Q4: What is the stator supposed to do on a Harley bike?

A: The stator powers all the electronic components on the bike. Here we are talking about both the spark plug and the accessories, such as the GPS, the headlights, your stereo and so on.

Without a stator, the bike won’t be functional, because the spark plug won’t be able to facilitate the fuel-burning process.

Q5: Will a motorcycle run with a bad stator?

A: Yes, then no. A failing stator will first cause some issues such as misfiring and backfiring, and it could even be hard to start the bike.

If left unsolved, the stator will eventually stop working completely, and the spark plug won’t be able to create sparks anymore, meaning your bike won’t start at all.


Bad stators can be hard to deal with, but what’s harder is making sure it’s the stator that’s causing the problems and not other components, such as the spark plugs or the battery.

You should consider each symptom explained in this article. Last but not least, it would not be a bad thing to do a test to ensure that you do not turn your attention to the wrong component.

Check the YouTube videos for a tutorial on how to do a test.