Engine misfires are the worst. Nothing ruins a good ride faster than your Harley sputtering and losing power. Often, the culprit is a worn-out or incorrect spark plug. Getting the right spark plugs can make a huge difference in your bike’s performance, fuel efficiency, and overall reliability. I’ve been wrenching on Harleys for years, and I’ve seen firsthand how much difference a good set of plugs can make. Let’s explore some top options to keep your hog running smoothly.
Here’s a quick rundown of the spark plugs we’ll be looking at:
- NGK DCPR7E Spark Plug: A reliable, all-around performer.
- Champion Copper Plus Spark Plug: A classic choice for older Harleys.
- Autolite 416 Spark Plug: Budget-friendly with good performance.
- E3 Spark Plug E3.31: Designed for improved combustion and power.
- SplitFire SF416D Spark Plug: Unique design for enhanced spark.
Top 5 Best Spark Plugs For Harley Davidson
1. NGK DCPR7E Spark Plug
The NGK DCPR7E is a popular choice for a reason. These plugs offer a great balance of performance, durability, and affordability. They’re known for their consistent spark and resistance to fouling, making them a reliable option for a wide range of Harley Davidson models.
Pros:
- ✅ Consistent performance
- ✅ Good resistance to fouling
- ✅ Widely compatible
Cons:
- ❌ May not offer significant performance gains over stock plugs
- ❌ Some users report shorter lifespan in high-performance engines
- ❌ Can be prone to counterfeit versions, so buy from trusted sources
Verdict: A solid, dependable choice for everyday riding and general maintenance. Great for riders who want a reliable plug without breaking the bank.
2. Champion Copper Plus Spark Plug
Champion Copper Plus plugs are a classic for older Harleys, particularly those with lower compression ratios. These plugs offer excellent thermal conductivity, helping to prevent overheating and pre-ignition. They’re a simple but effective option for keeping your vintage Harley running smoothly.
Pros:
- ✅ Excellent thermal conductivity
- ✅ Affordable price point
- ✅ Suitable for older, lower compression engines
Cons:
- ❌ May not perform as well in modern, high-performance engines
- ❌ Copper core wears faster than iridium or platinum plugs
- ❌ Requires more frequent replacement
Verdict: Best suited for older Harley models that benefit from the copper core’s heat dissipation properties. A good, budget-friendly option for vintage bikes.
3. Autolite 416 Spark Plug
If you’re looking for a budget-friendly spark plug that still delivers decent performance, the Autolite 416 is worth considering. These plugs are known for their reliability and consistent spark, making them a good option for riders who want to save money without sacrificing quality. I’ve used these in a pinch on my Sportster and was surprised how well they performed.
Pros:
- ✅ Very affordable
- ✅ Reliable spark
- ✅ Decent performance for the price
Cons:
- ❌ Shorter lifespan compared to premium plugs
- ❌ May not offer optimal performance in high-performance engines
- ❌ Basic construction
Verdict: A great option for riders on a budget who need a reliable spark plug for everyday riding. Perfect for stock or mildly modified engines.
4. E3 Spark Plug E3.31
The E3 Spark Plug E3.31 features a unique electrode design that’s intended to improve combustion efficiency and increase horsepower. These plugs are designed to provide a stronger, more consistent spark, which can lead to better fuel economy and improved throttle response. Some riders swear by them, claiming noticeable performance gains.
Pros:
- ✅ Unique electrode design for improved combustion
- ✅ Potential for increased horsepower and fuel economy
- ✅ May improve throttle response
Cons:
- ❌ Can be more expensive than traditional spark plugs
- ❌ Some users report inconsistent results
- ❌ The performance gains might be minimal on stock engines
Verdict: Worth a try if you’re looking for a potential performance boost. Best suited for riders who are willing to experiment and potentially see improved results.
5. SplitFire SF416D Spark Plug
SplitFire spark plugs are known for their distinctive split electrode design. This design is intended to create a larger spark kernel, which can lead to more efficient combustion. The SF416D is a popular choice for Harley riders who are looking for improved performance and throttle response. They look pretty cool, too!
Pros:
- ✅ Unique split electrode design
- ✅ Potential for improved combustion and throttle response
- ✅ Eye-catching appearance
Cons:
- ❌ Can be more expensive than standard plugs
- ❌ Some users report no noticeable performance difference
- ❌ May not be compatible with all Harley models
Verdict: A unique option for riders looking for potential performance improvements and a distinctive look. Worth considering if you’re willing to invest in a premium spark plug.
Buying Guide
Choosing the right spark plugs for your Harley Davidson involves considering a few key factors. Here’s what to keep in mind:
- Engine Type: Different Harley engines have different spark plug requirements. Check your owner’s manual or consult a mechanic to determine the correct plug type for your specific model.
- Heat Range: The heat range of a spark plug refers to its ability to dissipate heat. Using the wrong heat range can lead to pre-ignition or fouling. Again, your owner’s manual is your friend here.
- Riding Style: If you primarily ride short distances or in stop-and-go traffic, you may need a hotter spark plug to prevent fouling. If you ride long distances at high speeds, you may need a colder plug to prevent overheating.
- Engine Modifications: If you’ve modified your engine, such as adding a high-performance air filter or exhaust system, you may need to adjust your spark plug selection accordingly. Talk to a mechanic or performance shop for guidance.
- Budget: Spark plugs range in price from a few dollars to over twenty dollars each. Determine your budget and choose plugs that offer the best value for your money.
- Brand Reputation: Stick with reputable brands like NGK, Champion, Autolite, E3, and SplitFire. These brands have a proven track record of quality and reliability.
FAQs
Q: How often should I replace my spark plugs?
A: It depends on the type of spark plugs you’re using and your riding conditions. As a general rule, you should replace your spark plugs every 10,000 to 20,000 miles. However, it’s always a good idea to inspect your plugs regularly for signs of wear or fouling.
Q: What are the symptoms of bad spark plugs?
A: Common symptoms of bad spark plugs include engine misfires, rough idling, poor acceleration, decreased fuel economy, and difficulty starting the engine.
Q: Can I use a different type of spark plug than what’s recommended in my owner’s manual?
A: It’s generally not recommended to use a different type of spark plug than what’s specified in your owner’s manual. Using the wrong plug can lead to performance problems or even engine damage. If you’re unsure, consult a mechanic.
Q: Are expensive spark plugs worth the extra money?
A: It depends on your needs and priorities. Premium spark plugs may offer improved performance, fuel economy, or longevity. However, they may not be necessary for all riders. Consider your riding style, engine modifications, and budget when making your decision.
Q: How do I gap my spark plugs?
A: Spark plug gap is crucial. Use a spark plug gapping tool to measure the distance between the center electrode and the ground electrode. Adjust the gap according to the specifications in your owner’s manual. A properly gapped plug ensures optimal spark and combustion.
Conclusion
Choosing the best spark plugs for your Harley Davidson can seem overwhelming, but it doesn’t have to be. By considering your engine type, riding style, budget, and brand reputation, you can find the perfect plugs to keep your bike running smoothly. Whether you opt for the reliable NGK DCPR7E, the budget-friendly Autolite 416, or the performance-oriented E3 Spark Plug E3.31, make sure to choose plugs that are compatible with your specific model and riding needs. And remember, regular maintenance and inspection are key to keeping your Harley in top condition. Happy riding!
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