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If you’ve been riding for at least a decade, you probably know the struggle of spark plugs. It was even worse to work with these some forty years ago when they got wiped out fast.
People back in the day had to carry spare spark plugs in their pockets. Today, the technology has advanced, allowing manufacturers to make more reliable and long-lasting spark plugs for motorcycles.
Take a few minutes to discover the best-selling spark plugs for motorcycles and how to choose one that fits your needs and preferences. These are the best that the market offers, but keep in mind the motorcycle you ride.
6 Top Rated Spark Plugs for Motorcycles Reviewed
E3 Spark Plugs – Durable
This one is designed to provide a healthy power boost, enhancing the overall performance of your engine. It has a double DiamondFire ground electrode, enhancing the combustion pressure.
As a result, the plug improves fuel economy, reduces emissions, enhances power output, and allows faster starts.
Since it allows faster flame ignition, you’ll notice your bike performs smoother when it comes to acceleration and idle. Also, the colder heat ranges allow the spark plug to handle different intense conditions in the motor.
Still, one thing to keep in mind is that this one may not fit if your original spark plugs have a large gap. In most cases, it works for snowmobiles, gasoline-powered cars, watercraft, chainsaws, trucks, and nearly all Harley Davidson motorcycles.
NGK – Zinc Dipped
This NGK plug has a solid copper core that allows faster and more reliable sparks. The zinc-dipped shell provides additional durability and longevity, protecting against corrosion and rust.
The longer insulator nose prevents fouling, which adds even more to its overall durability. Plus, there are corrugated ribs on the insulator, preventing flashover.
Its triple gasket seal is one of its best features because it eliminates combustion gas leakage. It’s a significant pro of this product.
The built quality and its strong copper core allow better heat dissipation along with conductivity. Another thing worth noting is that its electrodes are dual ground, which helps to achieve a more reliable and consistent spark.
It’s a fairly compatible product and a good fit for most motorcycles. By far, it’s the most popular choice for Suzuki bikes.
Denso – Long Life
Denso is one of the first companies to use iridium, which is now a widely used chemical element. These are typically found in luxury cars such as Mitsubishi, Toyota, Honda, and GM.
The revolutionary 360° laser-welding process allowed Denso to create a unique spark plug. It’s among the best to improve your fuel economy, fix engine misfires, and improve acceleration.
It’s a pioneer when it comes to iridium spark plugs, showcasing reliability, fitment, and functionality regardless of the bike you ride.
However, it’s always the best to check compatibility so that you’re sure that Denso will fit your vehicle.
One thing to keep in mind is that this one comes in a pack of four. It’s a great value, allowing you always to have an extra plug at hand.
ACDelco – Smooth Performance
You can find ACDelco parts in more than two million GM vehicles each year. The Iridium spark plug offers better engine idle stability along with improved performance.
Also, it allows for more efficient, but smaller electrodes that improve cold starting and overall quicker acceleration.
The iridium electrode helps to improve your ignition, burning away carbon deposits that form on the tip of the plug. This helps to improve the overall fuel economy.
Another thing worth noting is the one-piece suppressor seal that blocks radio frequencies that can affect your bike’s electronics. The seal allows longer electrode life and seals in the case of combustion leakage.
This one is rather durable and resistant against wear, so it’s suitable for commuters and other bikers who ride often.
Pulstar – Innovative Plasma
Pulstar uses innovative plasma-assisted combustion technology to provide improved throttle response and increased horsepower.
The technology is already used in race cars, but it’s pretty expensive. Pulstar brings it to consumers at a more affordable price.
These have an internal capacitor, creating a high-intensity electrical pulse. This ionizes the air-fuel mixture while saturating it with combustion-enhancing plasma.
With this, they ignite fuel instantly, delivering superior throttle response. More precisely, you can gain up to 7 horsepower along with 9 ft-lbs of torque. It’s among the best choices for immediate, cold starts.
You can also expect to experience better miles per gallon, lower emissions, and smoother idle. This, however, depends on the motorcycle you ride, so make sure to double-check the compatibility.
Fram – Leak-proof
Fram Autolite 104 Copper Resistor Spark Plug is an ideal choice if you’re looking for better fuel economy, quick starts, and smooth acceleration.
Its copper-glass seal bonds insulation combined with terminal post center electrode create a gas-tight seal that is fully leak-proof.
The shell is made of cold-formed steel and precision rolled threads. The one-piece terminal post adds to the overall strength and durability.
Its multi-rib insulator reduces the chance of flashover, preventing misfires, and allowing safer use. Also, the resistor reduces radio frequency interference, preventing electrode erosion as well.
The core electrode is also made of copper, allowing better performance regardless of the conditions. Keep in mind that these come in a pack of four, although you can purchase them as singles as well.
What to Consider in Buying a Spark Plugs for Motorcycles
As you know, different motorcycles require different spark plugs. Figuring out what size is the best for your motorcycle isn’t at all as tricky as you may think. And while some are considered a standard, others may require a bit of measuring.
Use the diameter of the threaded area to measure the size. If you get this wrong, you may end up with a product that you can’t use.
Each vehicle has a different engine design, which is why you have to be careful about the plug you choose. An incorrect diameter won’t allow you to tighten it properly.
Compatibility depends on many things, such as the size, electrode gap, heat range, and a few others. The best way of figuring out if the spark plug is compatible with your bike is to look for that information from the manufacturer.
Most brands list bikes that they’re compatible with. If you can’t find precise compatibility information, you should find out the make and model of your motorcycle, as well as information about the engine and the fuel system.
The more information you collect, the easier it will be for you to choose accordingly.
Heat capacity is often called heat range as well. It’s the speed at which the plug transfers heat from the firing tip to the cooling system.
It’s used to tell you the amount of time that it can withstand heat combustion before it’s damaged. In most cases, heat capacity is displayed in numerical figures, and you find that information in your owner’s manual.
Most models have a heat capacity of 900 to 1,500° Fahrenheit. One thing to keep in mind is that you may need some help from an expert if you have a modified engine.
The electrode gap is another specification you should pay attention to. It refers to the distance between the ground and center electrodes. Keep in mind that the ground electrode is always 0 volts.
Once the center electrode reaches the correct voltage, it releases an electrical discharge as a spark. This ignites the fuel and moves the pistons.
The important thing to remember is that this has to be precise. If not, it can create a number of problems such as misfires, bad fuel economy, power loss, and an overall reduced lifespan. If you don’t know how to gap the plug precisely, you should consider a pre-gapped one.
Spark plugs have a certain role when it comes to how your motorcycle performs. However, some are better than others, thanks to the several features they come with.
Think about all the features that the spark plug comes with and how that can help your engine’s performance.
The best ones are usually the most functional ones. These offer better power efficiency, ignition time, and fuel economy.
Another great way of figuring out the functionally is to look at the pros and cons of each spark plug. This way, you can compare what you get and why you have to sacrifice.
Quality is always important when looking for new components for your motorcycle. The same goes for spark plugs, so make sure to look for the most reliable ones only.
The first thing you should look for is longevity. You want it to withstand the test of time even if you ride every day. Also, you want it to be safe to use on a particular bike you have.
One of the best ways to ensure quality is to find more information about the brand. Sometimes, you can learn a lot about a product by looking at the brand and customer reviews.
Those that are below $20 are usually the cheapest. These are typically nickel- or copper-tipped and have good corrosion resistance. You can find high-quality products at this price range. Many of them are pre-gapped and can resist pre-ignition as well.
Those that range from $20 to $90 usually feature materials like iridium, platinum, and also copper. In most cases, these are pre-gapped and are made to prevent electrode burnouts for excessive heat combustion.
Although they’re more expensive, they’re also more likely to offer smooth performance without engine misfires. Think about the price range that works the best for you, but try not to sacrifice important features for a lower price.
This is another critical factor to consider. You should know that the number of threads determines the level of reach into the combustion chamber.
If you have only a few threads, you probably won’t get such good combustion because the spark can’t project into the chamber.
On the other hand, too many threads could result in damage once the engine is running. You may also experience the fuel igniting sooner than you expect.
The best way to figure out the right size is to compare it to your bike’s original plug.
What You Need to Know
You should try to understand what a spark plug is and how it works so that you can find the best one for your motorcycle.
The mixture of vaporized fuel and air in the engine is compressed once it’s drawn into the cylinder by the piston. It then becomes highly flammable and even explosive. So, it explodes once ignited, slamming the piston back, which results in power.
The plug creates the spark that then creates the ignition. It’s generated in between the center and ground electrodes that we mentioned earlier in the article.
Double- or Single-Grounded
In most cases, you’ll come across double- and single-grounded spark plugs to choose from. The difference is in the number of ground electrodes that are next to the center one.
Keep in mind that more electrodes ensure longer life of your spark plug. It’s a more reliable option since there are more electrodes to rely on in case one wears out.
However, these have a setback, and in most cases, it’s not-so-great fuel efficiency.
Spark Plug Reach
Spark plug reach is a vital thing to consider. It tells you how far a plug can project the spark into the chamber. As we mentioned, the number of threads can affect the overall reach. In other words, if it has more threads, it’s more likely to have a better reach as well.
Failing to go deep enough into the combustion chamber results in poor combustion. On the other hand, going way too deep may result in damage.
Fixed or Adjustable Gap
Also, you may have noticed that some plugs have a fixed gap, while others are adjustable. A fixed gap is always in place, and you don’t have the convenience of adjusting it.
Adjustable gaps allow you to alter them in any way that works the best for you. In most cases, you can go with either, but make sure to consider both types.
There are several electrode types, as you probably noticed from our reviews above. Choosing between them typically comes down to your preference, although there’s some compatibility to think about as well.
Also, some are cheaper than others, so make sure to consider them all, keeping in mind the price range you’re okay with.
Copper-tipped plugs are probably the most common. They’re as popular because copper is among the best electricity conductors. For this reason, these don’t overheat as easily.
These are pretty long-lasting and usually affordable. A copper-tipped plug can last you some 40,000 miles before it starts to erode.
Iridium isn’t such a great electricity conductor. However, that doesn’t compromise the performance as much as you’d expect it to.
Interestingly enough, iridium plugs can often outlast copper ones, offering a service life of some 60,000 miles.
One thing to keep in mind is that these are expensive. Iridium is a tricky metal to find, which is why these are somewhat costly.
Platinum plugs are less conductive than copper but are still more expensive. These last longer, which justifies the price for the most part.
Also, these don’t wear out or erode as quickly and easily as copper. In most cases, these can last up to 100,000 miles. However, they’re more likely to have overheating problems.
Top Spark Plug Brands
Denso is a Japanese brand, leading the industry since 1972. It uses high-end, cutting-edge technology, making OEM equipment for Honda, Ford, Toyota, Volvo, Mercedes Benz, and General Motors.
It’s definitely one of the best options on the market since it’s a well-known name with lots of experience.
ACDelco is a subsidiary company of General Motors. It was founded in 1916 with current headquarters in Grand Blanc, Mich.
Much like Denso, it’s a reliable company that offers plenty of different products. As such, it offers parts for all kinds of motorcycles and other vehicles.
NKG is another Japanese company with more than 80 years of experience. It makes OEM and aftermarket accessories for the aviation and automotive industries.
Apart from spark plugs, the company makes ignition coils and oxygen sensors as well. It’s a reliable option since it has plenty of experience and customers to speak for its quality.
E3 Spark Plugs
E3 is an eco-friendly choice since the plugs offer complete and clean fuel burn. The company makes products for motorcycles, but also lawnmowers, ATVs, race cars and snowmobiles.
These are easy to find and use, and you’ll notice that they’re pretty affordable as well, depending on the type you need.
Benefits of Buying a Spark Plug for Motorcycle
Better Engine Performance
As you noticed, we mention engine performance quite often in our reviews. It’s one of the primary roles of a spark plug.
The best plugs produce enough spark to burn the mixture of air and fuel properly and efficiently. This is why it’s important to go for a quality one as it helps to prevent slipped firing and early ignitions.
However, most perform quite well when they’re brand new, but you want the performance to stay at its peak throughout the use.
A quality spark plug does a great job of transferring excess heat from the ignition chamber to the cooling system of the engine.
However, only the best ones can ensure a cool engine at all times. This may not seem as important at first, but it’s one of the most critical things to consider if you love long-distance trips.
Improves Starting Power
Everybody wants maximum starting power, but it’s unlikely you can experience anything nearly as impressive without a healthy spark plug.
A foul product may not start the bike at all. If this happens, you may want to check the gap because it could be too large, enabling the spark to ignite the combustion system.
The best way to ensure the ultimate starting power is to go for a healthy, high-quality plug that’s the most compatible with your motorbike.
Change Burnt Spark Plug
Having a reliable spark plug at hand allows you to change a burnt one the moment you need one. A burnt one won’t ignite the engine, which means you won’t be able to move the bike at all.
You’ll know that it’s burnt because it’s probably discolored at the negative probe. Measuring the gap between the center and the ground electrodes, you can notice that it’s wider than usual. The probe will burn away unless you replace it, causing the engine to misfire.
Maintains Fuel Health
When a plug is healthy, it helps your motorbike to maintain sufficient starting power. In turn, it saves the amount of fuel that your engine is going to burn.
It’s meant to burn off contaminants and deposits from additives found in the fuel. As a result, you’ll have fewer emissions from the motorbike.
Frequently Asked Questions
How often should I change my spark plug?
This largely depends on the quality and type you go for. For this reason, it’s critical that you choose a product that’s compatible with the particular motorcycle you have.
In most cases, plugs last some 6,000 to 7,000 kilometers. Still, you should check them from time to time even if you’re not as near to the 7,000 km mark.
What is the recommended heat range?
Most manufacturers say that the heat range should be between 500 and 850 degrees Celsius. However, manufacturers usually display the heat range so that you know if it fits your needs.
Choosing the right range is quite important, so make sure to give it a good thought. Unless you get this right, you’ll experience power loss and pre-ignition.
Can I change my own spark plug?
You can save some money by changing your own spark plugs. The process is rather simple and easy to learn, even if you don’t have any previous experience.
You’ll need compatible spark plugs and a few tools. On top of that, you also need a basic understanding of the process and what your goal is.
At this point, you probably know all it takes to find the right motorcycle spark plug. As we mentioned, one of the most critical things to pay attention to is compatibility. The product you choose has to be compatible with your motorbike, or it may not work as well, if at all.
However, make sure to consider other things we discussed in our buyer’s guide. The information can help you choose the best plug if you haven’t already.
The ones we reviewed are the top of what the market offers. These brands are reliable and known to make the best parts for motorcycles.