Installing bigger tires is often the first modification ATV owners want for their bikes. Bigger is always better, right? Well, before you go ahead and place an order for a new set of rubber, there are a few things to consider. As you will see, the biggest and most aggressive tires may not be the best option for everyone.
Can You Put Larger Tires on Your ATV?
When you’re thinking about switching to bigger tires, it’s essential to keep in mind that the manufacturer chose the stock tire size specifically to fit the engine size, suspension geometry, driveline strength, and transmission setup of that ATV model.
Changing to bigger tires will affect the carefully designed proportions between these components out of balance, potentially causing reduced overall performance, premature wear, or even sudden component failure.
But is there any wiggle room, or are you stuck with the stock tires?
Most ATVs can take tires one to two inches larger in diameter than stock without modifying the vehicle. However, even bigger tires usually require modifications to prevent rubbing, loss of torque, premature driveline- and drive belt wear and correct offset gear ratio.
This means if your stock tires are 26 inches in diameter, a 27 inch and probably a 28-inch tire as well should not cause any significant issues that trigger a need for extensive modifications.
So if you’re looking for slightly better off-road performance without breaking the bank on expensive mods and upgrades, you are better off not deviating more than one or two at the tops from the stock tire diameter.
But what if you want to go even bigger? What are the potential issues you run into, and how do you solve them?
Bigger Tires May Cause Clearance Issues
When trying to install oversized tires on a stock ATV, the first thing you’ll notice is that the tires will catch on the bike’s bodywork, undercarriage components, frame, brake lines, or other parts inside the bike’s wheel well.
A bigger tire may not cause rubbing on smooth terrain. But at soon as things get rougher and the tire starts bouncing up and down in combination with sharp turns, problems begin to arise.
The front wheels are typically going to rub first because they usually move around more. With the rear tires, the exhaust muffler often gets in the way first, along with the fender flares.
There are a few modifications you may consider doing to the bike to combat this issue:
Trim the fenders. When increasing tire size by two to three inches, you may get away by trimming off the outer portion of the plastic wheel fenders. I find that an angle grinder with a standard cutting disk makes for nice and clean cuts, but other cutting tools such as a jigsaw will probably work as well.
Install a lift kit. This mod is the most common and considered the best option to gain more clearance to fit bigger wheels and tires. Lift kits come with all the parts you need to increase the ride height of your ATV. You can get kits that raise the bike to anything from one to six inches or more.
The kits are not usually not universal, so you’ll need a kit that’s specifically made for your brand and model of ATV. Within the kit’s spec sheet, you’ll often find information on the maximum size tires you’ll be able to fit when the kit is installed.
The smallest kits typically consist of spacers, custom brackets, and the required longer bolts. They cost anything from $50 to $200.
As you go up in size, the kits become more comprehensive and also more expensive. A four or six-inch lift kit typically consists of lift brackets, spring spacers, custom A-arms, more durable axles, heavy-duty tie rods, extended brake lines as well as the required mounting hardware. Expect to pay from $200 to $2000 or more.
Install wheel spacers. The final option to gain better clearance in the wheel wells is by installing wheel spacers. Wheel spacers are metal discs that bolt onto the wheel studs to move the wheel outwards. You can get spacers in sizes ranging from ¼ inch to three inches or more, but I do not recommend getting spacers wider than two inches at the tops.
While wheel spacers offer a quick and easy way to increase clearance, they come with their share of drawbacks.
As the wheel is moved further outward from the wheel hub, the ATV becomes increasingly harder to steer and adds more strain, and causes more wear to the undercarriage components and driveline.
Check this post to learn more about the pros and cons of installing wheel spacers on your ATV.
Bigger Tires Cause Loss of Torque
One of the significant downsides of installing bigger tires is a loss of torque. This happens mainly because of the bigger circumference and because bigger tires typically weigh more.
While ATVs over 500cc may pack enough power to handle tires two inches larger in diameter, ATVs smaller than 500cc may begin to struggle already with a one-inch taller tire.
Using a tire with a longer circumference is almost like installing a high gear kit on the ATV or always running it in a slightly too high gear. And a heavier tire means the engine needs to use more power only to turn the tire which leaves less power for acceleration.
To gain some torque back, you can install a clutch kit or a gear reduction kit.
A Clutch kit will be the best alternative for those that go up one or two inches in tire size and like to ride fast. The kit uses stiffer springs to change at what RPMs the clutching phase happens. It’s like recalibrating the clutch to match the bigger wheels. A quality clutch kit will set you back around $300.
A gear reduction kit is likely the best option for those that go up no more than two to three inches in tire size but go slow for the most part. This category of riders will be those that are into rock crawling or those that do a lot of technical riding. There are two main types of gear reduction kits on the markets: portal gearboxes mounted on each wheel hub or internal transmission gear reduction kits.
A Clutch kit AND a gear reduction kit may be required if you go up more than three inches in tire size.
Bigger Tires Put Extra Strain on the Drive Belt
A bigger tire’s added weight and longer rolling circumference put more strain on the clutch belt and shorten its service life. You can reinforce your clutch by installing a heavy-duty drive belt. They do cost more but may save you both money and agony down the line.
Bigger Tires Put More Stress on the Driveline and Suspension
Heavier and larger diameter tires not only put more strain on the drive belt. In fact, the whole driveline will need to work harder. The CV joints are particularly prone to premature wear because of the added strain and because the joints have to work at an increased angle due to the added height.
Consider installing heavy-duty axles and CV joints to make them last longer and reduce the risk of them failing when your big tires suddenly catch traction as you spin them at full throttle in deep mud. Upgraded shocks will keep the added weight of the tire in check as it bounces up and down on uneven terrain.
Bigger Tires Make the ATV More Likely to Tip
While better ground clearance is one of the main reasons people install bigger tires and lift kits on their ATV, it’s essential to understand how it affects the bike’s stability. As the frame, engine, and body lift from the ground, so does the center of gravity.
An ATV with a high center of gravity may become top-heavy and more likely to tip when cornering or going up or down steep hills.
To combat this issue, you have three main options to choose from:
Get wheels with a wider offset. The offset of a wheel tells you where the wheel’s centerline is located in relevance to the outer surface of the wheel hub. The offset can be negative, zero, or positive, and the wheel center shifts further out as the offset decreases. Let’sLet’s say your stock wheel has an offset of -10mm. By installing wheels with an offset of -20 instead, the wheel shoots 10mm further out from the ATV, making the bike more stable when cornering.
Install a lift kit with a wider stance. Some more extreme lift kits include wider A-arms and longer axles that move the wheel hub further out than stock. The spec sheet of the kit should include information on how much the kit widens the ATV. While this is likely the best option to make an ATV wider and more stable, it is also the most expensive.
Install wheel spacers. If new wheels do not fit your budget, you can always install wheel spacers to achieve much of the same effect.
Bigger Tires or the Required Mods May Void the Warranty
Note that some manufacturers have placed certain restrictions because of some of the issues that may come with installing bigger tires.
While a small increase of one to two inches is usually allowed, you should always check the warranty terms to ensure that the wheels and modifications you are planning are permitted.
Why Do People Want Bigger Tires on Their ATVs?
Stock tires offer decent overall performance in a wide variety of riding applications ranging from utility work, high-speed trail riding to rock crawling and mud riding.
However, no one tire offers optimal performance in all of these scenarios. If you want extreme performance when you go mud bogging, you’ll need completely different tires than the need for excellent grip when rock crawling.
That is why most people want bigger tires; to optimize performance in specific riding conditions.
Better traction and flotation in wet mud, snow, or sand. Bigger tires with a more aggressive thread pattern typically offer better flotation and traction in wet conditions.
Better ground clearance. The added ground clearance gained by installing bigger tires lets you clear stumps, rocks, or other obstacles that would otherwise leave you high-sided.
A more aggressive look. Other riders want bigger tires because they think it looks meaner, more aggressive, and better in general.
How to Choose the Right Tire Size for You
While huge tires may look cool, they may not be the best option for you. You need to carefully consider what type of riding you’ll be doing the most. Then, use these guidelines to choose:
Utility work and occasional recreational riding. For most types of utility work and the occasional off-road experience, the stock tires will provide an ideal balance between traction, flotation, maneuverability, and performance.
Rock crawling and technical riding in rough terrain. You may want to increase the tire size slightly to increase the ground clearance for any technical riding. However, tires more than two inches from stock may case too much of a negative effect on stability and maneuverability in rough terrain. Also, the aggressive thread pattern found on some of the largest ATV tires is not beneficial for traction on hard and rocky surfaces.
Mud bogging in waist-deep mud or muskeg. If you’re building a dedicated mudding machine, you generally want to go as big as your wallet, and the bike’s engine can handle. Those that live and breathe for this type of riding often choose 30 to 34-inch tires with enormous lugged tread patterns to paddle through the mud.
Trail- and dune riding. In this type of riding, you typically want to go fast. A taller tire may cause too much of a negative impact on torque for it to be worth it. However, if you do a lot of dune riding, consider a wider tire or even a dedicated paddle-style sand tire.
Does ATV Tire Width Matter?
In some riding applications, the tire width matters more than the tire height.
In deep mud, you want a tall and narrow tire so that it’ll cut through the wet upper layer and into the firm underground for traction.
However, you’d want a wide tire on sand and in deep snow for better flotation and traction without sinking too deep into the surface.
What Are the Biggest ATV Tires?
The biggest ATV tires currently on the market are the Super ATV Terminators measuring a massive 34x10x15.
Can You Install Only Bigger Front ATV Tires?
The front and rear tires on most if not all ATVs are the same height. On a 4×4 ATV, you should never increase or decrease the height of only the front or the rear tires, as this may damage the bike’s transmission. The rolling diameter of both the front and rear tire needs to stay the same in relation to each other.
The tire width, however, is a different store. While changing the width of either the front or rear tires likely won’t cause any transmission issues, there are good reasons why the front tires on an ATV are smaller (narrower) than the rear.