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Choosing the Right Spark Plug for Your 1996-2008 Arctic Cat Bearcat Widetrack

Don't get left in the cold—picking the correct spark plug is critical for your Bearcat's engine.

4 minutes to read 1996-2008 Arctic Cat Bearcat Widetrack
Difficulty
1/5
Est. Time
0.25 hrs
DIY Doable?
✅ Yes
Shop Labor
$25-$50
⚠️ Drivable, but... — You can, but a misfiring or bogging engine could leave you stranded, and running with a fouled plug can cause unburnt fuel to wash oil from cylinder walls, increasing wear.
Key Takeaways
  • First, identify your engine: The correct plug depends on if you have a 2-stroke (440/550) or 4-stroke (660/660 Turbo) engine.
  • Use the right part number: For 2-strokes, use a standard NGK BR9ES. For 4-stroke turbos, you must use an iridium NGK KR8AI.
  • Always check the gap: Before installing, verify the spark plug gap is correct for your model (0.028" for BR9ES, ~0.032" for KR8AI).
  • Carry spares: Especially on 2-stroke models, plugs are cheap and easy to change on the trail. Carrying two new, gapped plugs is wise.
The spark plug in your Arctic Cat Bearcat Widetrack is a small but essential part. It creates a high-energy spark in the engine's combustion chamber. This spark ignites the mixture of air and fuel, creating the explosion that pushes the piston and powers your snowmobile. A good, clean spark plug ensures your engine starts easily, runs smoothly, and burns fuel efficiently. Whether you have a 2-stroke or 4-stroke Bearcat, the right spark plug is key to reliable performance on the trail.

The Most Important Step: Identify Your Engine

The 1996 to 2008 model years for the Bearcat Widetrack included several different engines. The correct spark plug is not based on the year, but on the specific engine in your sled. Before buying, you must know if you have a 2-stroke or a 4-stroke engine.

  • 2-Stroke Engines (e.g., 440cc, 550cc): These are common in the earlier models. They require a specific type of spark plug designed for engines that burn an oil-and-gas mixture.
  • 4-Stroke Engines (e.g., 660cc, 660cc Turbo): Found in later models, these engines have a separate oil system and use spark plugs similar to a car. The turbocharged models have unique requirements due to higher cylinder pressures and temperatures.

Check Your Engine First

Using the wrong spark plug can lead to poor performance, engine damage, or leave you stranded. Always confirm your engine size (e.g., "550" or "660 Turbo" on the hood or tunnel) before purchasing a new plug.

Choosing the Right Aftermarket Spark Plug

For the Bearcat Widetrack, "aftermarket" doesn't mean lower quality. Brands like NGK are often the Original Equipment Manufacturer (OEM), meaning they made the plug for Arctic Cat in the first place. The key is choosing the correct part number and type for your engine.

For 2-Stroke Bearcat Models (440cc & 550cc)

The standard and most recommended plug for these engines is the NGK BR9ES. These engines are designed to run on this simple, reliable, and inexpensive copper plug.

  • Brand Tier 1 (Recommended): NGK BR9ES. This is the workhorse plug and the one your engine was designed for.
  • Brand Tier 2 (Equivalent): Champion RN2C, Denso W27ESR, and Autolite 4062 are direct cross-references that will also work well.
  • Premium Plugs (Iridium/Platinum): While plugs like the NGK BR9EIX exist, they are often unnecessary for these 2-stroke engines. They cost significantly more and may not provide a noticeable benefit. Fouling from the oil/gas mixture can ruin an expensive plug just as easily as a standard one. Stick with the standard copper plug and change it regularly.

What about BPR9ES vs. BR9ES?

You may see a BPR9ES plug available. The "P" stands for "Projected Tip," which means the center electrode sticks out a bit further. While some riders use them, it's safest to stick with the non-projected BR9ES that was originally specified to avoid any potential piston clearance issues.

For 4-Stroke Bearcat Models (660cc & 660cc Turbo)

The 4-stroke engines, especially the turbo models, are more sensitive. They require a specific iridium spark plug to handle the heat and pressure. The correct plug is the NGK KR8AI.

  • Brand Tier 1 (Required): NGK KR8AI. This is an iridium plug specified for the 660 and 660 Turbo engines. Do not substitute this for a standard copper plug.
  • Brand Tier 2 (Equivalent): Other major brands may offer a direct cross-reference, but given the critical nature of the plug in a turbo engine, sticking with the specified NGK part is the safest choice.

Cost of New Aftermarket Spark Plugs

CategoryPrice Range
Standard Copper Plug (e.g., NGK BR9ES)$3.35 - $8.00
Iridium Plug (e.g., NGK KR8AI)$13.00 - $33.95
OEM Branded Plug from Dealer$10.00 - $25.00

Frequently Asked Questions

How often should I change my spark plugs?

For 2-stroke models, it's good practice to install a new set of plugs at the beginning of each season or every 1,000 miles. They are inexpensive and fouling is common. For 4-stroke models using iridium plugs, you can go much longer, typically 3,000-5,000 miles, but check your owner's manual for the specific interval.

What is spark plug "gapping" and is it important?

The "gap" is the small space between the center and ground electrodes. The spark must jump this gap. The distance is critical for proper ignition. Always check the gap with a feeler gauge or gap tool before installation. For the BR9ES, the gap should be around 0.028 inches. For the KR8AI, the gap should be around 0.031-0.032 inches.

What are the signs of a bad spark plug?

Common symptoms include difficulty starting, a rough idle, the engine running on only one cylinder, bogging down under acceleration, backfiring, and increased fuel consumption. A visual inspection may show a wet, black, or sooty plug (fouled) or a worn-out electrode.

Can I just clean my old spark plugs?

While you can sometimes clean a lightly fouled plug to get you home, it's a temporary fix. Given the low cost of standard plugs for 2-stroke models, replacement is always the better option. For expensive iridium plugs, cleaning is not recommended as you can easily damage the fine-wire tip.

Technical Specifications

OEM Part Numbers: BR9ES KR8AI

2-Stroke Engines (440cc, 550cc): - Standard Plug: NGK BR9ES - Spark Gap: 0.028 in (0.7mm) 4-Stroke Engines (660cc, 660 Turbo): - Standard Plug: NGK KR8AI (Iridium) - Spark Gap: 0.031-0.032 in (0.8mm)

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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

Year Coverage
This article covers the Spark Plug for:
  • Arctic Cat Bearcat Widetrack: 1996199719981999200020012002200320042005200620072008
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