Shopping for ATV wheels can be a daunting experience with all the specs and sizes to consider. Luckily, the different terms and how to use them are not as difficult as you might think.
In this post, we’ll be looking at the different ATV wheel sizes and specs, how to read them, and what you need to do to ensure you choose the right size for your ATV.
The terms we’ll cover are:
- Wheel size: Width and diameter
- Bolt pattern: Lug hole spacing
- Wheel offset and Backspacing
- Valve stem size
First: Rim vs. Wheel
Before we begin, just a quick note on wheel terminology.
The terms wheel and rim are often used interchangeably as if they mean the same thing. But technically speaking, a wheel and rim are not the same,
- The wheel is the entire metal part that a tire mounts to.
- The rim is the outmost portion of the wheel; it’s everything outside the spokes.
So when people talk about ATV rim sizes, they usually refer to the wheel as a whole, not just the rim part of the wheel. In this article, we’ll be only using the term wheel.
What Do the Advertised ATV Wheel Numbers Size Mean?
When you find a set of wheels you like and get to choose what size to get, you’re typically presented with a wheel sizing like this example:
14X8 6+2 4/115
- The first two numbers, separated by a multiplying (X) symbol, are the wheel size (diameter and width).
- The third and fourth numbers, separated by a plus (+) symbol, indicate the wheel offset.
- The fifth and sixth numbers, separated by a dash (/), are the wheel’s bolt pattern.
We’ll continue to use this example of wheel sizing throughout the article as we explain the different metrics in more detail.
ATV Wheel Size: Diameter and Width
The size of an ATV wheel consists of two metrics, diameter and width, and is measured in inches. Your typical ATV wheel or rim has a diameter of 12 to 14 inches and is 7 to 9 inches wide.
A wheel size of 14X8, as in our example, is pronounced: “14 by 8”. The wheel diameter is always located before the “X” and the width after; Diameter X Width.
ATV Wheel sizes vary depending on the ATV category and engine size.
- Youth ATVs: 6 to 10 inches in diameter and 6 to 7 inches wide.
- Racing Quads: 9 to 10 inches in diameter and 5 to 10 inches wide.
- Utility and Recreational ATVs: 12 to 14 inches in diameter and 7 to 11 inches wide.
More often than not, you will find that the rear wheels are wider than the front wheels. Please refer to the owner’s manual for recommended wheel sizes for your specific ATV model.
The wheel diameter is the distance between the bead seats on the widest point, measured straight across the center of the wheel.
A common mistake people make is measuring the overall wheel diameter from edge to edge, which is incorrect and will provide a reading about one inch bigger than the actual size.
The wheel diameter needs to correspond with what diameter tire will fit on the wheel.
Some wheels have taller rim sections than others, so that the outer edge would make for an inaccurate reference against the various tire sizes.
To ensure compliance across wheel and tire brands, the manufacturers need to use a metric that stays the same on all same-size wheels, which is why they use the bead seat diameter.
As a general rule, you should use the same diameter tire as your ATV came with.
If you’re looking to upgrade to a bigger wheel and tire, you can typically go up one or two inches in size without any modifications to the vehicle.
Note that you usually cannot go down in size from stock as a smaller diameter wheel cause the wheel to hit the brake calipers.
The wheel width is the distance between the bead seats, measured from where the seat meets the flange inside the rim.
People measuring tire width often make a similar mistake as when measuring wheel diameter. Rather than measuring on the inside, they measure the overall width from the outer edge to the outer edge.
This method is incorrect and will provide a reading about one inch wider than the correct wheel width. The inside measurement is more relatable when it’s time to find a tire that will fit on the wheel.
Remember that if you replace your stock wheels with wider aftermarket wheels, you will likely need to choose a different wheel offset (see below).
A wider wheel with the same offset will protrude longer into the wheel well, potentially causing rubbing issues.
Also, most ATVs come with skinnier wheels front than rear. But most aftermarket wheels have the same width wheels front and back (you can still use different width tires front and back).
In that case, you need to remember the front and rear wheel offset needs to be different to compensate for the difference from the stock setup.
Bolt Pattern (Lug Spacing)
The bolt pattern is a metric indicating the number of wheel lugs or bolt holes and the spacing between them, known as Pitch Circle Diameter (PCD) or bolt circle.
ATV wheels typically come in 3-lug, 4-lug, and 5-lug configurations. The bolt spacing, PCD, typically varies between brands and engine sizes.
PCD is measured as the diameter (in millimeters) of an imaginary circle that runs through all the wheel bolts. The method to measure PCD varies depending on how many bolt holes there are.
Our example wheel from the beginning of this article has a bolt pattern of 4/115, which tells us that it has four holes for wheel bolts or wheel studs and a PCD of 115mm.
If you want to learn more about bolt patterns, I recommend our dedicated post, where we go more in-depth.
And if you want to learn more about wheel bolts, lug nuts, wheel studs, and the difference between them, I’ve also made a dedicated guide on that.
Wheel Offset and Backspacing
Wheel offset is the one metric that confuses ATV wheel buyers the most. Some of the confusion may be because the Powersports industry has adopted a different way of stating offset than the automotive industry standard.
While it’s slightly more complicated than more straightforward concepts like diameter and width, you should be able to make sense of it in a minute.
On most vehicles, the offset is measured in millimeters, known as the ET number, which measures the distance from the hub mounting surface to the wheel’s geometrical centerline.
However, on ATVs, the offset is usually provided as two numbers in an A+B format where A is the distance from the inner bead seat to the mounting surface and B is from the mounting surface to the outer bead seat.
The sum of A+B is always the same as the tire width. Our example from above has an offset of 5+2, which gives us a wheel width of 7 inches.
The purpose of wheel offset is to determine how far inward or outward the wheel sits relative to the wheel hub.
If the wheel sits too far in, the tire will rub against suspension components, brake lines, or the inner wheel well panels. The rubbing will lead to a reduced turning radius, poor handling, and damage to the tire and the components it rubs.
And if the wheel sits too far out, the wheel bearing will wear faster, and the ATV becomes harder to steer.
Wheel offset can be negative, neutral, or positive.
- A negative offset is when the mounting surface sits inside the wheel’s centerline.
- Neutral offset is when the mounting surface lines up with the centerline.
- A positive offset is when the mounting surface sits outside the centerline.
ET number offset uses a (-) sign to indicate a negative offset. For example, ET-25 means the mounting surface sits 25mm inside the wheel’s centerline.
On ATV offset, you can determine if the offset is positive, neutral, or negative by which number is the biggest.
- The offset is positive if the first number is bigger than the last one, like in our example (5+2).
- The offset is neutral or zero if both numbers are equal (3,5+3,5).
- If the first number is smaller than the last, the offset is negative (2+5).
Backspacing is the distance from the mounting surface to the rear edge of the wheel. This metric determines how far the wheel protrudes inside the wheel well and whether there is enough clearance to prevent rubbing.
This was only the short version. I’ve dedicated an entire post on offset and backspacing if you want a more in-depth explanation.
The wheel’s center bore is the large diameter hole in the center of the wheel, usually covered by a center cap. Its purpose is to help center the wheel on the wheel hub to prevent vibrations.
You’ll notice a circular flange on the wheel hub that protrudes about 5-10mm from the hub mounting surface. The center bore inner diameter should be the same as the wheel hub flange’s outer diameter.
Factory wheels are usually machined for an exact fit where the wheel fits snugly on the wheel hub.
However, aftermarket wheels usually have a larger diameter center bore to fit a broader selection of vehicles. The center bore is fitted with plastic hub centric rings with the same inner diameter as your vehicle’s wheel hub to ensure a snug fit and proper centering,
Valve Stem Size
The valve stem is the rubber part that holds the valve stem core and is where you inflate the tire with air after installing it onto the wheel.
Valve stems come in different sizes, and the one you choose must fit with the wheel’s corresponding hole to prevent leaks. You also need to consider valve stem length.
Most tubeless ATV wheels use valve stems with a diameter of 0.452 inches (11,5mm). Tire shops have all sizes of valve stems and will install the right one when you get the tires installed on the wheel.
Here is a more in-depth guide on getting the right valve stem and installing a valve stem to a wheel at home.
Most well-reputed ATV wheel manufacturers provide information about wheel weight in their wheel spec sheets. But why does wheel weight matter?
A lighter wheel can have a range of benefits, such as:
- Faster acceleration. Heavier wheels and tires require more engine power to turn.
- More consistent traction in rough and bumpy terrain as the suspension is better able to absorb the weight.
- More responsive handling as the power steering needs to shift less weight as you turn.
- Better braking. A lighter wheel is easier to stop with less weight in motion, causing shorter braking distances and reduced brake wear.
- Reduced strain and wear on suspension and undercarriage components.
If the seller doesn’t list the wheel weight, I would advise you to ask and compare your findings with other popular alternatives.
Other Relevant ATV Wheel Specs
Other specs wheel manufacturers usually provide are:
- The material type and quality. Steel and aluminum alloys are the most common wheel materials.
- Left / Right. Most wheels are universal, but if the wheels are for either left-side or right-side use, this should be listed in the specs.
- Vehicle type: Some manufacturers tell you whether the wheel is intended for utility or racing applications.
How do I know what size my ATV wheels are?
- Measure. Most of the relevant specs can be measured directly from your old wheels.
- Refer to the Owners manual. The user manual may have information about stock wheel sizes depending on the make and model.
- Ask your dealer.
ATV Rim Width vs. Tire Width
A common question amongst ATV wheel buyers is how wide the rim should be relative to the tires. As a general rule, it is advised to choose a wheel that is 1 to 4 inches more narrow than the wheels you plan on using.