6 Best Spark Plugs For Motorized Bicycle: Mechanical and Professional Experience Combined!

Best Spark Plugs For Motorized Bicycle

E3.36 Powersports Spark Plug is our top pick

A motorized bicycle, which is more like a cycle than a bike, often has an engine ranging from 49cc to 80cc, but not more than that. It can be either a two-stroke engine or a four-stroke engine.

So, in general, spark plugs designed for 50cc moped engines up to 80cc motorbike engines are pretty much applicable for motorized bicycles. That means you can easily select spark plugs from that category.

However, many well-known spark plug manufacturers, including NGK, Champion, Sten, and E3, produce excellent spark plugs for your vehicle’s engine.

As a result, we came up with the 6 best spark plugs for motorcycles after considering the best cost and performance, user feedback, and spark plug longevity. So, let’s read and find out which one is ideal for your motorized bicycle.

Another important thing that you must know is the type of spark plug. Basically, copper, iridium, and platinum are the three major types of spark plugs available in the shops. 

The main difference between copper spark plugs with iridium and platinum spark plugs is not their performance but their longevity. Iridium and platinum plugs last longer than copper plugs.

That’s why these two types are more costly than a copper plug. That’s why you will get the copper spark plug available at every shop rather than the iridium or platinum spark plug. And that’s all you should know about a spark plug.

Best Spark Plug for Motorcycle – Our Top 6 Picks!

Here are our top 6 picks of spark plugs for your motorized bicycle. This ranking is based on the most appealing qualities of each product we evaluated during the testing period.

E3.36 Powersports Spark Plug


“The copper core provides excellent heat transmission and contributes to the plug’s longevity.”

E3 Powersports E3.32 Spark Plug


“Designed to boost power, minimize fuel consumption, and reduce hydrocarbon emissions.”

NGK B6L Spark Plug


“Provides optimum dissipation of heat for more reliable starts with greater longevity at a reasonable price.”

ACDelco GM 41-114 Iridium Spark Plug


“Guarantees superior engine idle stability and reliable performance.”

Stens New 130-847 Spark Plug


“Provides dependability and high performance so that the engine runs smoothly.”

E3.20 Small Engine Spark Plug

“Extra Durable as longevity is extended by removing performance-inhibiting carbon deposits.”

What is a Motorized Bicycle

A bicycle that combines pedal power with internal combustion engine power is referred to as a “motorized bicycle.” It is a type of bicycle with an integrated engine that is used to propel the bicycle without pedaling or to help with pedaling. 

The motor or engine of a motorized bicycle could be a two-stroke or a four-stroke IC engine. It could also be an electric or diesel engine too. Electric motorized bicycles, or e-bikes, are most famous among riders.

The design of a motorized bicycle or motorcycle varies greatly, and each is intended for a specific purpose. Many motorized bicycles are able to propel themselves independently without pedaling. However, regardless of how powerful it is, it is often unable to reach speeds of more than 52 km/h.

What You Should Know About Spark Plugs

“Ignition of the air-fuel mixture in the combustion chamber is the main purpose of a spark plug.” It is common knowledge that we all have. But knowing about spark plugs doesn’t mean that at all. Perhaps, you have to know much more than that. Such as

Spark plugs are designed to explode whenever a cylinder burns, and each combustion cycle takes less than 0.01 percent of a second! To spark properly, it must be not only very efficient but also extremely durable so that it can be ignited hundreds of thousands of times without failing.

Also, spark plugs must work under extremely specific parameters for your engine, considering shape, the gap between the electrodes, which must be accurate to inches, and heat range.

Again, if the spacing or electrode gapping is not matched, you’ll have a lot of misfires, loss of power, plug fouling, poor fuel efficiency, and quicker wear — and nobody has time for that! So, the gapping must be ideal for your engine.

A Review of the 6 Best Spark Plugs for Motorized Bicycles

Spark plugs are one of those little elements that seldom attract attention anymore. So, evaluating these items was difficult for us because there were hundreds of options available to us, and we had a short amount of time to evaluate them all.

As a result, we chose some fundamental criteria so that we could evaluate each product on the same basis, taking into account all of the details that a standard spark plug should include. What we tested in detail are-

  • Does the spark plug fit in all possible engines?
  • Does it provide proper ignition?
  • Is the core material standard?
  • Does it have the proper plug gap?
  • Thread diameter
  • Fouling rate
  • The rate of fuel consumption
  • Life span
  • Service warranty
  • Retail Value
  • OEM approved or not
  • Which engine is perfect?

Let’s have a look at what we have on our list for you.

1. Editor’s Choice: E3.36 Powersports Spark Plug

Brand: E3 Spark Plugs | Weight: 1.6 ounces | Dimensions: ‎6.5 x 4.5 x 0.8 inches | Material: Copper

E3 Spark Plugs E3.36 Powersports Spark Plug

Bright Side

  • Fit almost every type of engines
  • Provides Quickstarts in all conditions 
  • Improve fuel efficiency 
  • 5 years’ service warranty

Not So Good Side

  • Short diameter thread
  • Over plug-spacing

Our first pick on the list is this E3.36 Powersports Spark Plug from E3. E3 Power Sports spark plugs represent a significant advancement in spark plug technology. More power, faster starts, improved fuel efficiency, and reduced emissions are all benefits of using power sports plugs. 

Does the spark plug fit in all possible engines of motorized bicycles?

This spark plug, according to E3, is a UNIVERSAL FIT type spark plug, which implies it may be used in any engine. So, we put it in our Silver Slant 80cc and Zeda 80 66cc two-stroke engines. In a nutshell, it works flawlessly in both engines. So, yes, it’s possible.

Proper Ignition

In comparison to other copper spark plugs we’ve tried; it does offer appropriate ignition. In addition, it comes with DiamondFire electrode technology, which produces a better spark and a flame front that extends longer into the cylinder, resulting in more controlled heat.

Core Material Standard

This is a copper spark plug, and copper is the standard core material because of its high thermal toleration rate. However, unlike other spark plugs, which contain 92 to 98 percent copper, this E3.36 Powersports spark plug appears to be odd. Its core is made of 100% copper. As a result, you might be able to get a good heat range.

Proper Plug Gap

The 0.04-inch spark plug spacing on this E3.36 spark plug is a little greater than we recommend. As a result, you can have problems like defective sparking or dual ignition. But it’s simply a guess based on our past experiences, as the window of opportunity is too small. 

Thread Diameter Accuracy

Small engines, such as bicycle motors, are built in such a way that they can plug long threads. In this case, it has a 12 mm thread, which is 1 mm smaller than the usual diameter. However, if you’re searching for the best spark plug for 80cc motorized bike, this size is standard.

Fouling Rate

Less than 4% is the ideal fouling rate of a standard spark plug, in experts’ suggestions. Here, this E3.36 Powersports spark plug stands at the top of our test. Compared to the NGK B6L spark plug, it has a lower fouling rate, which is around 2-3%.

Fuel Consumption Rate

Another unique feature of this spark plug is its ability to help enhance fuel economy. According to our test results, it can improve fuel efficiency by up to 10%. That implies you can get good mileage out of it.

Life-Span

For testing this feature, we consulted our trusted users who have been using this E3.36 power sports spark plug for at least two years. 

We took their plugs and checked the condition, which was completely satisfactory. In fact, without some grease, there was no damage to the plugs.

 So, barring any unforeseen circumstances, it has a long-life cycle.

Service Warranty

E3 will undoubtedly provide you with a 3-month servicing warranty for this spark plug. Of course, this is a positive sign. If you have a problem with your bicycle’s engine spark plug or want to update it, you may replace it.

Retail Value

Typically, a single purchase of copper or standard spark plugs costs between $5 to $8. So, We looked for the pricing of E3.36 spark plugs at various retailers, both physical and online. We identified the pricing range between $6 and $8, which is ideal for this sort of item.

OEM Approval

Yes, E3 is an original equipment manufacturer, and all of their items are OEM certified. 

Which engine is perfect?

We have tested this spark plug in several bicycle motors. According to our observation, it is the best spark plug for 2-stroke engines and performs better in 66cc to 80cc 2-stroke engines.

Another unique feature of this spark plug is that, depending on the engine class, emissions in 2- and 4-stroke engines are reduced after 50 hours of operation. It also reduces CO emissions by 58% and hydrocarbons by 42%, making it environmentally beneficial.

2. Best Spark Plug Overall: E3 Powersports E3.32 Spark Plug

Brand: E3 | Weight: 1.6 ounces | Dimensions: ‎6.4 x 4.35 x 1.05 inches | Material: Copper

E3 Spark Plugs E3.32 Premium Powersports Spark Plug

Bright Side

  • Appropriate plug spacing
  • Improved hydrocarbon emission
  • Optimal fuel consumption
  • Corrosion protected

Not So Good Side

  • Over-sized for small engines
  • Less service warranty

In the same price range and with almost akin features as the E3.36, we picked this E3.32 Powersports spark plug for our list. This one has proper plug gapping and thread diameter with all the necessary features we tested. That’s why we tagged this as the best overall.

Does the spark plug fit in all possible engines of motorized bicycles?

This spark plug, unlike the E3.36, does not tend to match all engines. However, we used this 14mm thread diameter plug in our Phantom and Zeda, and it suited nicely. Apart from a few exceptions, you can use it with any bicycle engine.

Proper Ignition

The E3.32 plugs stand out because of their innovative DiamondFIRE ground electrode. This electrode provides proper ignition by initiating faster flame propagation, resulting in a complete burn of the fuel mixture.

Core Material Standard

Among all earth materials, copper is one of the most heat-tolerant metals, which is why this metal is standard for the spark plug. So, this one can be considered a standard material plug. 

Proper Plug Gap

Although the ground electrode of this plug is patented DIAMONDFIRE type, its plug gapping is ideal, which is 0.03 inches. 

Thread Diameter

The common thread diameter for motorized bicycle motors is 12-14 mm. This one has a 14mm diameter thread, the largest in the line. As a result, it may be firmly fitted to the engines.

Fouling Rate

It is a matter of concern, of course. Well, its foul rate is close to 3%. Yet it’s below average. The average fouling rate of spark plugs is 3–4%, and we suggest not using any more than that.

Fuel Consumption Rate

This spark plug from the E3 Powersports series is facilitated to improve fuel economy. So, technically it is bound to provide a decent rate, and as per our test experience, we are convinced.

Life Span

Durability is one of the major concerns, and this one is durable enough in structure. In addition, its top and core materials are alloy steel and copper, which means it has both surface protection and core protection that indicate a long-life span.

Service Warranty

The E3 brand policy is to provide a 90-day service warranty on their Powersports series. And it genuinely works even if you use the plug for 89 days. You can claim the warranty on the 90th day if the condition matches.

Retail Value

According to our analysis, you can buy it for less than $8. It’s the usual value of a copper spark plug everywhere. But the price may vary, so you can visit Amazon to get the update.

OEM approval

This E3.32 Powersports spark plug is OEM certified. Basically, these products are compared to genuine ones for their authenticity.

Which engine is perfect?

This one is compatible with all types of bicycle engines, especially high-powered engines like the PHANTOM or SLANT.

3. Best Budget Spark Plug: NGK B6L Spark Plug

Brand: NGK | Weight: 1.92 ounces | Dimensions: ‎0.35 x 0.39 x 1.3 inches | Material: Copper

NGK Spark Plug, NGK B6L

Bright Side

  • Improved heat dissipation for reliable starts
  • Controlled overheating   
  • Cold-rolled threads to avoid cylinder head damage
  • Reasonable price

Not So Good Side

  • Low life-span
  • Misfire sometimes

NGK is a well-known brand of spark plugs, yet despite its popularity, this NGK B6L spark plug is a great value in a budget product.

Does the spark plug fit in all possible engines of motorized bicycles?

The NGK B6L is basically a resistor-type plug. Structurally, this one can fit into any engine socket except the racing ones. Racing engines require non-resistor-type plugs.  

Core Material Standard

This NGK B6L spark plug is made of copper. It has a 98 percent pure copper core that helps to dissipate heat and ensures optimum ignition for more consistent starts.

Proper Plug Gap

0.03 is the standard gap for any small engine, like bicycle or moped engines. And this spark plug gap is exactly the standard one.

Thread Diameter Accuracy

The thread diameter of this plug is 14mm. It’s the optimum diameter to fit any engine.

Fouling Rate

It has a fouling rate of 2% to 3% on average. The spark plug insulators are made of 99 percent pure alumina silicate, resulting in longer insulator noses and less fouling.

Fuel Consumption Rate

According to the manufacturer, this spark plug has a triple-gasket sealing method that prevents fuel leakage. Triple Seal gaskets are made for high-risk procedures that need a high level of operational safety. As a result, fuel efficiency improves due to power ignition and gasoline leakage reductions.

Life-Span

This spark plug is made of a long-lasting, corrosion- and abrasion-resistant substance. It has a resistor that is fired to guarantee that it performs well and lasts a long time. 

Service Warranty

One drawback of this spark plug by NGK is that it doesn’t provide any warranty. But we are taking this as guarantee of long durability as NGK is one of the giants in this category. 

Retail Value

This plug is the most cost-effective of the bunch. In fact, for a few dollars (no more than $5), you can acquire this. We had our doubts about the quality in contrast to the price, but it proved to be adequate.

OEM approval

All NGK products are OEM certified, including this NGK B6L spark plug.

Which engine is perfect?

Except for racing engines, this NGK spark plug fits practically all small engines, such as 49cc, 50cc, 66cc, and 80cc motorized bicycle engines.

4. Best Spark Plug for Performance: ACDelco GM 41-114 Iridium Spark Plug

Brand: ACDelco | Weight: 1.44 ounces | Dimensions: ‎‎4.4 x 3.5 x 1 inches | Material: Iridium

ACDelco GM Original Equipment 41-114 Iridium Spark Plug

Bright Side

  • Iridium core material for improved performance
  • Low Combustion Leakage
  • Long electrode life
  • Smooth and reliable performance

Not So Good Side

  • Small size that suits racing engines more
  • High price range than copper spark plugs

Iridium spark plugs are recognized for their long life and outstanding performance, which is exactly what this ACDelco GM 41-114 iridium spark plug offers.

Does the spark plug fit in all possible engines of motorized bicycles?

This ACDelco spark plug is designed in a conventional shape. It fits practically every type of motorized bicycle engine with its 12mm thread. This spark plug is designed to fulfill your needs in terms of fit, form, and function.

Core Material Standard

This one is an iridium spark plug. Iridium core material is the most durable material with a high melting point, extremely strong, and extremely wear-resistant. But, for a bicycle engine, it’s not that important.

Proper Plug Gap

Standard plugs have an optimal plug spacing dimension. Though it was not explicitly stated by the authorities, we attempted to measure it ourselves and found that it was close to 0.03 inches, which was convincing to regular riders because they had no problems with it.

Thread Diameter Accuracy

Like the plug spacing, this platinum spark plug has a 12 mm thread. Usually, we prefer 13–14 mm, but it also works well for small engines. Basically, 12 mm’s are designed to create extra pressure for rapid sparks in racing motors. That’s why a small diameter is used.

Fouling Rate

The one-piece suppressor seal assists in reducing combustion leakage by metering spark energy for long electrode life. As a result, the fouling rate remains below average.

Fuel Consumption Rate

Like all the spark plugs on the list, it also increases fuel economy. But the improvement in fuel economy was kind of invisible to us. So, we put this as an average rating.

Life-Span

As we mentioned before, iridium spark plugs are famous for their durability. We assume that you can ride with this plug for 150 thousand miles on average, but not less than 100 thousand miles. 

Service Warranty

There is no service warranty that you will get with this ACDelco GM 41-114 spark plug. But our assumption is that this “No Warranty” indicates a lifelong guarantee because its built-in quality is quite strong and durable.

Retail Value

The price of this iridium plug is two times greater than the NGK B6L spark plug. Unfortunately, it means you’ll have to spend an extra couple of dollars over the E3 standard plugs.

OEM Approval

ACDelco GM Original spark plugs are OEM certified. These spark plugs are developed, produced, and tested to the highest standards.

Which engine is perfect?

This spark is best for high-power racer engines, mostly non-resistor types.

5. Best Spark Plug for Quick Spark: Stens New 130847 Spark Plug

Brand: Stens | Weight: 1.76 ounces | Dimensions: ‎‎‎0.36 x 0.37 x 1.35 inches | Material: Copper

New Stens Spark Plug 130-847

Bright Side

  • OEM product
  • 1-year service warranty
  • Standard Thread Diameter
  • High ignition accuracy

Not So Good Side

  • High price than other plugs of its variety
  • Fouling rate of 6%

This STEN New 130-847 Spark Plug is quite similar to NGK spark plugs, but some features of this plug are better in comparison to the NGK B6L. Actually, it can be considered a replacement for NGK.

However, its 98 percent pure copper core allows for greater heat dissipation, resulting in more consistent and simple starts in all situations and a lower danger of overheating.

Does the spark plug fit in all possible engines of motorized bicycles?

This plug, like the NGK, is compatible with all types of motorized bicycle motors. In fact, when we took it with NGK, they both looked the same.

Core Material Standard

It features a copper core that is 98 percent pure. Because of its availability and capacity to be recycled, copper is frequently utilized as a core material. And you’ll find that 7 out of 10 spark plugs are made of copper.

Proper Plug Gap

Below standard, Its plug gapping is about 0.025 inches which technically can cause mis-sparking or duo misfires. Though we didn’t face anything like that, the standard is preferable in this case. But one can re-gap the plug using tools.

Thread Diameter Accuracy

 14 mm, the standard size for any resistor engine. Specially bicycle motors.

Fouling Rate

As we mentioned earlier, it’s plug gapping. It can cause fouling, but we didn’t notice any of its users complaining. But you can fix the fouling with regular maintenance of the plug.

Life-Span

This spark plug features a nickel alloy and metal covering with a copper core, indicating that it will last a long time. However, our calculations suggest that it will run for 120 thousand kilometers without a hitch.

Service Warranty

Every spark plug comes with a one-year warranty from Stens, ensuring dependability and performance. But if there are any issues, you may claim a replacement within one year of purchase.

Retail Value

Aside from all the top qualities, the price of this spark plug is a little more than that of other manufacturers with similar features. But the major point that we believe is credible is that Sten offers a one-year warranty, making it a secure investment.

OEM approval

Yes, it is OEM certified. Professionals rely on Stens branded spark plugs to make OEM-quality repairs.

Which engine is perfect?

Sten’s OEM-grade spark plug is virtually universally compatible and performs admirably in all engines.

6. Best Durable Spark Plug: E3.20 Small Engine Spark Plug

Brand: E3 | Weight: ‎1.76 ounces | Dimensions: ‎‎‎6 x 4 x 1 inches | Material: Alloy Steel

E3 Spark Plugs E3.20

Bright Side

  • Fit 4-stroke engines
  • One-size-fits-all type plug gap
  • Lower emission
  • High life-span

Not So Good Side

  • No service warranties
  • Perform optimally with small engines only

This E3.20 small engine spark plugs electrode and full-size center electrode gives maximum performance throughout a longer product life with amazing durability. Greater power, improved fuel efficiency, and drastically reduced hydrocarbon emissions are all advantages of using this spark plug.

Does the spark plug fit in all possible engines of motorized bicycles?

This spark plug is specially designed for small but powerful engines such as lawnmowers, garden tillers, and bicycle motors.

Core Material Standard

With a full-size center copper core, this spark plug holds an ideal performance record with high durability.

Proper Plug Gap

Its Diamond FIRE feature is a one-of-a-kind design with an edge-to-edge spark path and a 0.03-inch plug gap that enables fresh air charge replenishment of the spark zone.

Thread Diameter Accuracy

This plug features a 14mm plug thread diameter. So, it’s compatible with a variety of 4-cycle engines.

Fouling Rate

This E3.20 spark plug is engineered to deliver peak performance, lower fuel economy, and lower hydrocarbon emissions. In addition, its fouling rate is nearly non-existent.

Life-Span

By assessing all of the conceivable performance gaps and peaks, our testing results and experience show that this spark plug has a long-life duration, which can be up to 120 thousand miles.

Service Warranty

No service warranty we found with this product. Although other E3 series spark plugs are covered under warranty, this plug is not.

Retail Value

You can get this spark plug for half the price of the ACDelco GM 41-114 Iridium Spark Plug. The price per spark plug should be between 5-7 dollars. 

OEM approval

Spark plugs of E3 are obviously OEM-graded. And this product is also OEM certified.

Which engine is perfect?

The E3.20 small engine spark plug is the best fit for any variety of 4-cycle engines. Also, you can use it on any lawn mower or garden tiller engine for better performance.

FAQ

Based on our research and experience, we chose a few of the most important and commonly asked questions and attempted to respond to them. So, there you have it-

What is the best spark plug for a motorized bicycle?

There is no specific one-size-fits-all spark plug that is best for motorized bicycles. Different motors are used in different bicycles. However, we can recommend some specs in which you’ll get better performance. For example, you can use a spark plug with a 0.03-inch gap, a 14 mm thread, and an open ground electrode.

You surely know about the three major types of spark plugs: copper, iridium, and platinum. Here, we would like to suggest that you go for the copper plugs. It’s the standard type, and it comes with all of the necessary features, including quick spark, at a reasonable price.

What kind of spark plug does an 80cc bicycle motor take?

An 80cc motor is a highly powerful motor for a bicycle. It can reach a top speed than the average motorized bicycle does. That’s why we suggest you use any 80cc or above engine spark plug for this type of engine for better performance. For example, NGK’s resistor spark plugs like BR5HS, B6L, etc. 

From our list, the E3 Powersports E3.32 Spark Plug can be used for an 80cc bicycle motor. This one is efficient, reliable for top-grade performance, and environmentally safe also because it reduces 58 percent of CO- carbon monoxide emissions and hydrocarbons by 42%.

What is the spark plug gap on an 80cc motor?

On an 80cc motor, the spacing must be between 0.03-0.04 inches. But the 0.03 inches plug gap is preferable. You can adjust the gap using a plug-gaping tool.

The spark plug gap is the distance between the center electrode and the ground electrode, where the spark plug is designed to discharge. The spark plug may not always operate effectively in all gaps.

Additionally, improper spark plug spacing can cause erratic spark plug firing, resulting in delayed engine combustion and an engine that misses or idles unnaturally. For example, an over-gapped spark plug causes an engine to miss or run erratically.

How often should I change my motorized bicycle’s spark plug?

Changing a spark plug, either way, isn’t all that remarkable because it only has to be changed once in a while. It is dependent on the sort of bicycle engine you are using.

For example, A 49cc-66cc engine requires a replacement every 120,000 to 150,000 miles of operation. And the spark plug in an 80cc engine should be changed every 100 to 120 thousand miles.

But our suggestion is to check your spark plug in every 50,000 miles period. It will help you to maintain the spark plug for a long time without any replacement. In fact, through regular and proper maintenance, you can use a spark plug for half-time greater than average life.

Can you pedal a motorized bicycle?

You can, of course, pedal your motorized bicycle. Pedal your bicycle like any other bike when you want to get a workout in. Turn on the pedal-assist for uphill assistance or a long-distance break to receive motorized assistance with each pedal.

Many experts and doctors agreed that sitting in the same posture for more than 20 minutes might cause back discomfort, muscular loosening, and other problems. For better health, we recommend maintaining a steady flow of pedaling when riding your motorized bicycle.

Final Words

We hope that you have already found the ideal spark plug for your bicycle’s engine here. However, among our 6 best spark plugs for motorized bicycles, we would like to suggest the E3.36 Powersports Spark Plug and the ACDelco GM 41-114 Iridium Spark Plug for your motorized bicycle, as these two were quite reliable during our testing.

Even so, if you run into any problems, we’ve compiled a list of tips and recommendations to assist you. It might not be enough, but we hope it will be helpful to you. Again, if you find difficulties, you can visit your local mechanic for better suggestions.

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