Can Am Ds 90 Spark Plug – Your Complete DIY Replacement & Tuning Guide

There’s nothing quite like the sound of your kid’s Can-Am DS 90 firing up instantly, ready for a day of trail riding. But what happens when that eager roar is replaced by a sputtering cough, or worse, silence? You’ve checked the fuel, you’ve checked the kill switch, but the little beast just won’t cooperate. It’s a frustrating moment we’ve all faced in the garage.

We promise this guide will fix that. More often than not, the culprit behind these headaches is a tiny, inexpensive part: the Can-Am DS 90 spark plug. It’s the heart of your ATV’s ignition system, and keeping it in top shape is one of the easiest and most impactful DIY jobs you can do.

In this ultimate guide from the crew at FatBoysOffroad, we’re going to walk you through everything. We’ll cover how to spot a failing plug, how to choose the perfect replacement, and a full, step-by-step tutorial on how to change it yourself. Get ready to save money, gain confidence, and get that DS 90 running like new again.

Why Your Can-Am DS 90 Spark Plug is a Tiny Titan of Performance

It’s easy to overlook something so small, but that spark plug is doing some heavy lifting inside your engine. Think of it as the match that lights the fire. With every rotation of the engine, it delivers a high-voltage electrical spark that ignites the air-fuel mixture in the cylinder.

This single, perfectly timed spark is what creates the combustion that pushes the piston down, turns the crankshaft, and ultimately, sends power to the wheels. When that spark is strong and consistent, your ATV runs at its peak.

Understanding the benefits of a healthy Can-Am DS 90 spark plug makes it clear why this isn’t a part you want to neglect. A fresh, properly gapped plug is your ticket to:

Effortless Starts: A strong spark ignites fuel instantly, meaning less cranking and more riding.
Crisp Throttle Response: No more hesitation or bogging down when you hit the gas.
Maximum Power: Complete combustion extracts every bit of energy from the fuel, giving the little DS 90 all the pep it was designed for.
Better Fuel Economy: When fuel is burned efficiently, you’re not wasting it out the exhaust pipe. You’ll get more ride time out of every tank.
A Healthier Engine: A good plug prevents the buildup of carbon deposits that can harm internal engine components over time.

Telltale Signs: How to Know Your DS 90 Spark Plug is Failing

Your DS 90 will usually give you some warning signs before a spark plug completely gives up the ghost. Learning to recognize these symptoms can save you from being stranded on the trail. These are some of the most common problems with a Can-Am DS 90 spark plug that’s on its way out.

Keep an eye (and an ear) out for these classic indicators:

Hard Starting: This is the number one symptom. If you have to crank the engine over and over, especially when it’s cold, a weak spark is a likely cause.
Rough Idling: Does the ATV sound choppy or inconsistent when it’s just sitting there running? A misfiring plug can cause the engine to shake and stumble at idle.
Engine Misfires or Sputtering: While riding, you might feel the engine “hiccup” or lose power for a split second. This is a classic misfire, where the plug failed to ignite the fuel on a combustion stroke.
Poor Acceleration: If the DS 90 feels sluggish and doesn’t have the “get-up-and-go” it used to, the spark might not be strong enough to handle the increased fuel demand under load.
Increased Fuel Consumption: Are you filling up the tank more often than usual? An inefficient spark leads to wasted fuel, which hits you right in the wallet.
Fouled Appearance: The best way to know for sure is to pull the plug and look at it. If the tip is covered in black, sooty carbon or wet with oil or fuel, it’s time for a new one.

Choosing the Right Spark Plug for Your Can-Am DS 90

When it’s time for a replacement, walking into an auto parts store can be overwhelming. You’ll see plugs made of copper, platinum, and iridium, all at different price points. So, what’s the right choice?

For a stock Can-Am DS 90, the answer is simple: stick with the manufacturer’s recommendation. This is a key part of our Can-Am DS 90 spark plug guide. The engineers at BRP designed the engine to run perfectly with a specific type of plug.

The standard OEM plug for most model years of the DS 90 is the NGK CR7HSA. It’s a reliable, standard copper plug that provides excellent performance for this engine. You don’t need a fancy, expensive iridium plug unless you’ve done significant performance modifications to the engine.

Understanding Spark Plug Gap

Before you install a new plug, you MUST check the gap. The “gap” is the tiny distance between the center electrode and the ground electrode at the tip of the plug. The spark has to jump this gap to ignite the fuel.

For the Can-Am DS 90, the correct spark plug gap is typically 0.6mm to 0.7mm (0.024″ to 0.028″). Always double-check your owner’s manual for the exact spec for your model year.

Even brand-new plugs can get bumped in shipping, so never assume the gap is correct out of the box. Use a feeler gauge or a spark plug gap tool to measure it and gently adjust the ground electrode if needed.

How to Change Your Can-Am DS 90 Spark Plug: A Step-by-Step Guide

Alright, let’s get our hands dirty! This is one of the most satisfying DIY jobs you can do. Following this guide on how to change the Can-Am DS 90 spark plug will have you done in under 15 minutes.

H3: Tools and Parts You’ll Need

New Spark Plug: NGK CR7HSA or equivalent.
Ratchet Wrench: A standard 3/8″ drive is perfect.
Spark Plug Socket: A 5/8″ (or 16mm) deep socket, preferably with a rubber insert to protect the plug.
Socket Extension: A 3-inch or 6-inch extension will make life easier.
Spark Plug Gap Tool: A simple coin-style or feeler gauge tool.
Dielectric Grease: A small packet for the spark plug boot.
Anti-Seize Compound: Optional, but highly recommended for the plug threads.
A Rag: For cleaning the area.

H3: Step 1: Safety First & Prep Work

Before you touch anything, make sure the engine is completely cool. Working on a hot engine is a recipe for burned hands and seized parts. Park the ATV on a level surface.

Find the spark plug. On the DS 90, it’s typically on the left side of the engine cylinder head, easily accessible. Before you remove anything, use your rag or some compressed air to clean all the dirt and debris from around the base of the spark plug. You don’t want any of that gunk falling into your engine cylinder.

H3: Step 2: Accessing and Removing the Old Plug

Firmly grasp the black rubber cap on the end of the wire connected to the spark plug. This is the spark plug boot. Wiggle it back and forth gently and pull straight off. It might be on there snug, but don’t yank on the wire itself.

Place your spark plug socket and extension onto your ratchet. Fit the socket over the spark plug, making sure it’s seated all the way down. Turn the ratchet counter-clockwise (lefty-loosey) to break the plug free. It might take a little bit of force at first. Once it’s loose, you should be able to unscrew it the rest of the way by hand.

H3: Step 3: Reading the Old Spark Plug

Don’t just toss the old plug! This is one of our favorite Can-Am DS 90 spark plug tips. The condition of the old plug is like a health report for your engine.

Light Tan or Grayish-Brown: Perfect! This indicates your engine is running well with a proper air-fuel mixture.
Dry, Sooty Black: This means the engine is running too rich (too much fuel, not enough air). Check your air filter and carburetor settings.
White or Blistered: This is a sign of a lean condition (too much air, not enough fuel) or overheating. This can be very damaging, so investigate it immediately.
Wet with Oil: Oily deposits suggest there might be an internal engine issue, like worn piston rings or valve seals.

H3: Step 4: Gapping and Installing the New Plug

Grab your new spark plug and your gapping tool. Check the gap and adjust if necessary. This is one of the most important Can-Am DS 90 spark plug best practices.

Apply a very small amount of anti-seize compound to the threads of the new plug. This prevents it from getting stuck in the aluminum cylinder head. Carefully thread the new plug into the engine by hand. You must be able to turn it several full rotations easily. If you feel any resistance, stop immediately, back it out, and try again to avoid cross-threading.

Once it’s hand-tight, attach your socket and ratchet. Snug it down until it stops, then give it an additional 1/4 to 1/2 turn. Do not over-tighten! You can damage the plug or the cylinder head.

Finally, squeeze a small dab of dielectric grease into the opening of the spark plug boot. This ensures a good electrical connection and prevents corrosion. Push the boot back onto the top of the new spark plug until you feel or hear a solid “click.” That’s it, you’re done!

Pro Tips for Long-Lasting Spark Plug Performance

A little preventative maintenance goes a long way. Following a good Can-Am DS 90 spark plug care guide will keep your ATV reliable season after season.

First, check your plug periodically, maybe every other oil change. It only takes a few minutes and gives you valuable insight into your engine’s health.

Second, always keep your air filter clean! A clogged air filter is the number one cause of a rich fuel mixture, which quickly fouls spark plugs. A clean filter allows the engine to breathe properly, promoting a clean burn.

Finally, use quality fuel. Poor quality or old gas can leave deposits that foul plugs and clog up your carburetor. Stick to fresh fuel from reputable stations.

Spark Plugs and Sustainability: The Eco-Friendly Angle

You might not think of a spark plug as an environmental part, but it plays a surprisingly important role. A sustainable Can-Am DS 90 spark plug is one that is working at peak efficiency.

When the spark is strong and consistent, it ensures the air-fuel mixture in the cylinder burns as completely as possible. This process maximizes power and minimizes the amount of unburnt fuel and harmful hydrocarbons that get pushed out the exhaust.

By simply keeping a fresh plug in your DS 90, you are directly contributing to lower emissions and better fuel economy. It’s a small, eco-friendly Can-Am DS 90 spark plug practice that makes a real difference. A well-maintained machine is a cleaner machine.

Frequently Asked Questions About the Can-Am DS 90 Spark Plug

What is the correct spark plug for a Can-Am DS 90?

For most model years, the standard, manufacturer-recommended spark plug is the NGK CR7HSA. It’s always best to confirm with your owner’s manual, but this is the go-to plug for a stock engine.

How often should I change the spark plug on my DS 90?

A good rule of thumb is to replace the spark plug at the beginning of every riding season or every 50 hours of use, whichever comes first. They are inexpensive, and it’s cheap insurance against starting problems.

What is the correct spark plug gap for a Can-Am DS 90?

The correct gap is typically between 0.6mm and 0.7mm (0.024″ and 0.028″). Always use a proper gapping tool to measure and set the gap on a new plug before installation.

Can I clean and reuse an old spark plug?

While you can technically clean a lightly fouled plug with a wire brush in a pinch, we don’t recommend it as a long-term solution. Spark plug electrodes wear down over time, widening the gap and creating a weaker spark. Given how affordable new plugs are, replacement is always the better option.

Tackling this job yourself is a fantastic way to get more familiar with your machine and build your confidence as a DIY mechanic. That little spark plug holds the key to reliability and performance, and now you have all the knowledge you need to keep it in perfect working order.

Now, go grab your tools, get that DS 90 running right, and hit the trails. Stay safe and have fun out there!

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Thomas Corle

Founder & Automobile expert at FatBoysOffroad

Automobile expert and off-road enthusiast, sharing in-depth knowledge of vehicles, gear, and adventures. Helping readers make smart decisions and enjoy the thrill of off-roading safely and confidently.