1. Motorcycle Spark Plugs For Sale
  2. sku: 14047041995003663
  3. HARLEY DAVIDSON 31963-04

HARLEY-DAVIDSON 31963-04 Front Rear Spark Plug Set

fits model: Xl1200, Sportster. make: Harley. year: 2004–2006.

31963-04 Harley-davidson 04-06 Sportster Xl1200 Front Rear Spark Plug Set

( Brand: Harley-davidson ), ( Manufacturer Part Number: 31963-04 ), ( Type: Spark Plug Wires ), ( Country Of Origin: United States ), ( Color: Black ), ( Manufacturer Warranty: Unspecified Length ), ( Placement On Vehicle: Inner ), ( Storage Location: E.4.f.3 K462115-c ), ( Custom1: 210993 ), ( Material: Rubber, Plastic ), ( Machine Type: Street Motorcycle ), ( Vintage Part: No )

Review HARLEY DAVIDSON Front Rear Spark Plug Set fits SPORTSTER XL1200 2004–2006

The **Harley-Davidson 31963-04 OEM Spark Plug Set (2004-2006 Sportster XL1200)** is a precision-engineered component designed to deliver optimal performance, reliability, and longevity for Harley-Davidson s iconic XL1200 Sportster models produced between 2004 and 2006. Crafted to Harley-Davidson s exacting specifications, this genuine OEM spark plug set ensures seamless ignition, smooth power delivery, and consistent combustion efficiency, which are critical for maintaining the distinctive throttle response and torque characteristic of the Sportster s legendary V-twin engine. Each plug in this set features a **NGK CR8HS** configuration, a proven choice for Harley-Davidson s air-cooled, high-compression engines, where precise heat range and electrode design are essential for preventing fouling while maximizing combustion efficiency. The **copper core construction** provides superior heat dissipation, reducing the risk of pre-ignition or misfires, particularly under heavy loads or in high-temperature conditions, ensuring that your XL1200 runs with the same punchy, responsive power it was engineered for. Beyond performance, these plugs are built to withstand the demands of Harley-Davidson s durable yet high-revving engine architecture, offering extended service life between replacements and minimizing the need for frequent maintenance. Whether you re a weekend cruiser, a track enthusiast, or a rider who demands nothing less than factory-level performance, this OEM spark plug set is the ideal choice for preserving the authenticity and power of your Sportster while ensuring trouble-free operation. Properly gapped and installed according to Harley-Davidson s recommendations, this set will help maintain your bike s original performance standards, contributing to a smoother ride, better fuel economy, and the satisfying growl of a properly tuned V-twin.

**Pros and Cons of buying a Harley-Davidson 31963-04 (2004-2006 Sportster XL1200 Front & Rear Spark Plug Set)**

### **Pros:**

1. **OEM Quality and Compatibility** This is a genuine Harley-Davidson part, meaning it is designed specifically for the XL1200 Sportster engine. Using OEM components ensures proper fit, performance, and longevity, reducing the risk of misfires or engine issues.

2. **Reliability and Durability** Harley-Davidson spark plugs are built to withstand the demands of motorcycle engines, including high temperatures and electrical loads. The XL1200 s air-cooled, pushrod engine benefits from well-maintained plugs, which help prevent fouling and ensure consistent ignition.

3. **Easy Installation** Spark plugs are straightforward to replace, requiring minimal tools and time. The set includes both the front and rear plugs, so you won t need to purchase them separately, saving effort and potential confusion.

4. **Prevents Engine Misfires and Performance Loss** Worn or fouled spark plugs can cause rough idling, hesitation, or poor acceleration. Replacing them as part of routine maintenance keeps the engine running smoothly and maintains power output.

5. **Cost-Effective Maintenance** While not the cheapest aftermarket option, OEM plugs are a reasonable investment compared to potential engine damage from neglect. They also tend to last longer than some budget alternatives.

6. **Warranty Coverage** If purchased directly from Harley-Davidson or an authorized dealer, the part may still be under warranty, providing added peace of mind.

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### **Cons:**

1. **Higher Upfront Cost** Compared to aftermarket spark plugs, OEM parts from Harley-Davidson are more expensive. For budget-conscious riders, third-party brands (like NGK or Denso) may offer similar performance at a lower price.

2. **Limited Availability Outside Dealers** While not impossible, genuine Harley parts may be harder to find at non-dealer retailers or online marketplaces compared to generic spark plugs. This could require ordering from the manufacturer or an authorized seller.

3. **Potential Overkill for Routine Maintenance** If you re replacing plugs as part of a regular service interval (e.g., every 10,000 15,000 miles), OEM plugs may not be necessary unless you prefer using only factory-specified parts.

4. **No Performance Upgrade** Unlike some aftermarket plugs designed for higher compression or performance tuning, OEM plugs are optimized for stock engine specifications. They won t improve power or throttle response beyond stock levels.

5. **Mixed Reviews on Longevity** Some riders report that OEM Harley plugs wear out faster than high-quality aftermarket alternatives, especially in high-mileage or heavily modified engines. This can lead to more frequent replacements.

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### **Conclusion:**

The **Harley-Davidson 31963-04 spark plug set** is a solid choice if you prioritize **reliability, compatibility, and peace of mind** for your 2004 2006 XL1200 Sportster. It s the safest option for ensuring your engine runs optimally, especially if you prefer sticking to factory-recommended parts. However, if cost is a concern or you re comfortable with aftermarket brands, reputable alternatives like **NGK (97522) or Denso (UK922)** offer comparable performance at a lower price without sacrificing quality.

For most riders, the **pros outweigh the cons**, particularly if you value OEM support and long-term engine health. That said, if you re on a tight budget or plan to replace plugs frequently, exploring aftermarket options could be a more economical solution.

### **Recommendation:**

- **Buy the OEM set** if you want the most reliable, hassle-free option and don t mind paying a premium for Harley s brand assurance.

- **Consider aftermarket alternatives** (e.g., NGK or Denso) if you re looking to save money while maintaining high performance and longevity.

- **Follow the manufacturer s maintenance schedule** (typically every 10,000 15,000 miles or as needed) to avoid misfires and engine stress.

- **Check for genuine Harley parts** from authorized dealers or trusted online retailers to avoid counterfeit or subpar replicas.

Details:

Fits 2004 - 2006 Harley-Davidson Sportster XL883 and XL1200 model's Custom, Low, Roadster. OEM 31963-04. Spark Plug Wires - Front and rear ignition cable set with protective corrugated loom rubber boots. Good working condition, boots are intact.

Part is off a Good Running 2006 Harley-Davidson Sportster XL12 Watch Video of this Unit - YouTube. 04-06 Harley Sportster XL1200 Driver Passenger Seat 51530-04.

part #: 3196304 price

  • $32.49

specifications cyclesparkplugs:

  • for models: Xl1200, Sportster
  • for makes: Harley
  • for years: 2004-2006
  • brand: Harley-davidson
  • mpn: 31963-04
  • type: Spark Plug Wires
  • country of origin: United States
  • color: Black
  • manufacturer warranty: Unspecified Length
  • placement on vehicle: Inner
  • storage location: E.4.f.3 K462115-c
  • custom1: 210993
  • material: Rubber, Plastic
  • machine type: Street Motorcycle
  • vintage part: No

payments cyclesparkplugs:

  • credit card: Diners-club
  • wallet: Apple-pay
  • other

returns cyclesparkplugs:

  • paid by: Buyer
  • policy: Returns Accepted
  • time: 30 Days

seller cyclesparkplugs:

  • city: Odessa, Florida
  • rating: 99.4%
  • # reviews: 217775

offer cyclesparkplugs:

  • availability: In Stock
  • started: March 24, 2026
  • options: Ship-to-home
  • quantity: 1
  • sold: 0

general cyclesparkplugs:

  • condition: Used
  • Motorcycle Scooter Parts Accessories > Electrical Ignition Components > Spark Plugs

shipping cyclesparkplugs:

  • type: Fixed
  • carrier: USPS, FedEx
  • class: Standard, Expedited, One-day
  • cost: $0.00
  • transit: 3-8 Days
  • service: USPS Ground Advantage, USPS Priority Mail, FedEx 2Day, Overnight
for models: xl1200, sportster, for makes: harley, for years: 2004-2006, type: spark plug wires, country of origin: united states, manufacturer warranty: unspecified length, placement on vehicle: inner, storage location: e.4.f.3 k462115-c, custom1: 210993, machine type: street motorcycle, vintage part: no,
category: motorcycle parts > motorcycle scooter parts accessories > electrical ignition components > spark plugs, color: black, material: rubber, plastic, sku: 14047041995003663,
Harley-davidson 31963-04 Is Similar To:
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1 offer $32.49 USD
  • Used. Offer #1 priced at $32.49 + $0.00 shipping estimate = $32.49* total. Part is off a Good Running 2006 Harley-Davidson Sportster XL1200. Spark Plug Wires - Front and rear ignition cable set with protective corrugated loom and rubber boots.FREE SHIPPING

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